Western philosophy

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Western philosophy

History of Western philosophy from its development among the ancient Greeks to the present.

 

Modern philosophy



Modern philosophy » The rise of empiricism and rationalism

The scientific contrast between Vesalius’s rigorous observational techniques and Galileo’s reliance on mathematics was similar to the philosophical contrast between Bacon’s experimental method and Descartes’s emphasis on a priori reasoning. Indeed, these differences can be conceived in more abstract terms as the contrast between empiricism and rationalism. This theme dominated the philosophical controversies of the 17th and 18th centuries and was hardly resolved before the advent of Immanuel Kant.

Modern philosophy » The rise of empiricism and rationalism » The empiricism of Francis Bacon

Sir Francis Bacon was the outstanding apostle of Renaissance empiricism. Less an original metaphysician or cosmologist than the advocate of a vast new program for the advancement of learning and the reformation of scientific method, Bacon conceived of philosophy as a new technique of reasoning that would reestablish natural science on a firm foundation. In the Advancement of Learning (1605), he charted the map of knowledge: history, which depends on the human faculty of memory, poetry, which depends on imagination, and philosophy, which depends on reason. To reason, however, Bacon assigned a completely experiential function. Fifteen years later, in his Novum Organum, he made this clear: Because, he said, “we have as yet no natural philosophy which is pure,…the true business of philosophy must be…to apply the understanding…to a fresh examination of particulars.” A technique for “the fresh examination of particulars” thus constituted his chief contribution to philosophy.

Bacon’s hope for a new birth of science depended not only on vastly more numerous and varied experiments but primarily on “an entirely different method, order, and process for advancing experience.” This method consisted of the construction of what he called “tables of discovery.” He distinguished three kinds: tables of presence, of absence, and of degree (i.e., in the case of any two properties, such as heat and friction, instances in which they appear together, instances in which one appears without the other, and instances in which their amounts vary proportionately). The ultimate purpose of these tables was to order facts in such a way that the true causes of phenomena (the subject of physics) and the true “forms” of things (the subject of metaphysics—the study of the nature of being) could be inductively established.

Bacon’s empiricism was not raw or unsophisticated. His concept of fact and his belief in the primacy of observation led him to formulate laws and generalizations. Also, his conception of forms was quite un-Platonic: a form for him was not an essence but a permanent geometric or mechanical structure. His enduring place in the history of philosophy lies, however, in his single-minded advocacy of experience as the only source of valid knowledge and in his profound enthusiasm for the perfection of natural science. It is in this sense that “the Baconian spirit” was a source of inspiration for generations of later philosophers and scientists.

 

Francis Bacon, Viscount Saint Alban British author, philosopher, and statesman also called (1603–18) Sir Francis Bacon born Jan. 22, 1561, York House, London, Eng. died April 9, 1626, London Overview British statesman and philosopher, father of modern scientific method. He studied at Cambridge and at Gray’s Inn. A supporter of the Earl of Essex, Bacon turned against him when Essex was tried for treason. Under James I he rose steadily, becoming successively solicitor general (1607), attorney general (1613), and lord chancellor (1618). Convicted of accepting bribes from those being tried in his court, he was briefly imprisoned and permanently lost his public offices; he died deeply in debt. He attempted to put natural science on a firm empirical foundation in the Novum Organum (1620), which sets forth his scientific method. His elaborate classification of the sciences inspired the 18th-century French Encyclopedists (see Encyclopédie), and his empiricism inspired 19th-century British philosophers of science. His other works include The Advancement of Learning (1605), History of Henry VII (1622), and several important legal and constitutional works. Main lord chancellor of England (1618–21). A lawyer, statesman, philosopher, and master of the English tongue, he is remembered in literary terms for the sharp worldly wisdom of a few dozen essays; by students of constitutional history for his power as a speaker in Parliament and in famous trials and as James I’s lord chancellor; and intellectually as a man who claimed all knowledge as his province and, after a magisterial survey, urgently advocated new ways by which man might establish a legitimate command over nature for the relief of his estate. Life » Youth and early maturity Bacon was born Jan. 22, 1561, at York House off the Strand, London, the younger of the two sons of the lord keeper, Sir Nicholas Bacon, by his second marriage. Nicholas Bacon, born in comparatively humble circumstances, had risen to become lord keeper of the great seal. Francis’ cousin through his mother was Robert Cecil, later earl of Salisbury and chief minister of the crown at the end of Elizabeth I’s reign and the beginning of James I’s. From 1573 to 1575 Bacon was educated at Trinity College, Cambridge, but his weak constitution caused him to suffer ill health there. His distaste for what he termed “unfruitful” Aristotelian philosophy began at Cambridge. From 1576 to 1579 Bacon was in France as a member of the English ambassador’s suite. He was recalled abruptly after the sudden death of his father, who left him relatively little money. Bacon remained financially embarrassed virtually until his death. Life » Youth and early maturity » Early legal career and political ambitions In 1576 Bacon had been admitted as an “ancient” (senior governor) of Gray’s Inn, one of the four Inns of Court that served as institutions for legal education, in London. In 1579 he took up residence there and after becoming a barrister in 1582 progressed in time through the posts of reader (lecturer at the Inn), bencher (senior member of the Inn), and queen’s (from 1603 king’s) counsel extraordinary to those of solicitor general and attorney general. Even as successful a legal career as this, however, did not satisfy his political and philosophical ambitions. Bacon occupied himself with the tract “Temporis Partus Maximus” (“The Greatest Part of Time”) in 1582; it has not survived. In 1584 he sat as member of Parliament for Melcombe Regis in Dorset and subsequently represented Taunton, Liverpool, the County of Middlesex, Southampton, Ipswich, and the University of Cambridge. In 1589 a “Letter of Advice” to the Queen and An Advertisement Touching the Controversies of the Church of England indicated his political interests and showed a fair promise of political potential by reason of their levelheadedness and disposition to reconcile. In 1593 came a setback to his political hopes: he took a stand objecting to the government’s intensified demand for subsidies to help meet the expenses of the war against Spain. Elizabeth took offense, and Bacon was in disgrace during several critical years when there were chances for legal advancement. Life » Youth and early maturity » Relationship with Essex Meanwhile, sometime before July 1591, Bacon had become acquainted with Robert Devereux, the young earl of Essex, who was a favourite of the Queen, although still in some disgrace with her for his unauthorized marriage to the widow of Sir Philip Sidney. Bacon saw in the Earl the “fittest instrument to do good to the State” and offered Essex the friendly advice of an older, wiser, and more subtle man. Essex did his best to mollify the Queen, and when the office of attorney general fell vacant, he enthusiastically but unsuccessfully supported the claim of Bacon. Other recommendations by Essex for high offices to be conferred on Bacon also failed. By 1598 Essex’ failure in an expedition against Spanish treasure ships made him harder to control; and although Bacon’s efforts to divert his energies to Ireland, where the people were in revolt, proved only too successful, Essex lost his head when things went wrong and he returned against orders. Bacon certainly did what he could to accommodate matters but merely offended both sides; in June 1600 he found himself as the Queen’s learned counsel taking part in the informal trial of his patron. Essex bore him no ill will and shortly after his release was again on friendly terms with him. But after Essex’ abortive attempt of 1601 to seize the Queen and force her dismissal of his rivals, Bacon, who had known nothing of the project, viewed Essex as a traitor and drew up the official report on the affair. This, however, was heavily altered by others before publication. After Essex’ execution Bacon, in 1604, published the Apologie in Certaine Imputations Concerning the Late Earle of Essex in defense of his own actions. It is a coherent piece of self-justification, but to posterity it does not carry complete conviction, particularly since it evinces no personal distress. Life » Career in the service of James I When Elizabeth died in 1603, Bacon’s letter-writing ability was directed to finding a place for himself and a use for his talents in James I’s services. He pointed to his concern for Irish affairs, the union of the kingdoms, and the pacification of the church as proof that he had much to offer the new king. Through the influence of his cousin Robert Cecil, Bacon was one of the 300 new knights dubbed in 1603. The following year he was confirmed as learned counsel and sat in the first Parliament of the new reign in the debates of its first session. He was also active as one of the commissioners for discussing a union with Scotland. In the autumn of 1605 he published his Advancement of Learning, dedicated to the King, and in the following summer he married Alice Barnham, the daughter of a London alderman. Preferment in the royal service, however, still eluded him, and it was not until June 1607 that his petitions and his vigorous though vain efforts to persuade the Commons to accept the King’s proposals for union with Scotland were at length rewarded with the post of solicitor general. Even then, his political influence remained negligible, a fact that he came to attribute to the power and jealousy of Cecil, by then earl of Salisbury and the King’s chief minister. In 1609 his De Sapientia Veterum (“The Wisdom of the Ancients”), in which he expounded what he took to be the hidden practical meaning embodied in ancient myths, came out and proved to be, next to the Essayes, his most popular book in his own lifetime. In 1614 he seems to have written The New Atlantis, his far-seeing scientific utopian work, which did not get into print until 1626. After Salisbury’s death in 1612, Bacon renewed his efforts to gain influence with the King, writing a number of remarkable papers of advice upon affairs of state and, in particular, upon the relations between Crown and Parliament. The King adopted his proposal for removing Coke from his post as chief justice of the common pleas and appointing him to the King’s Bench, while appointing Bacon attorney general in 1613. During the next few years Bacon’s views about the royal prerogative brought him, as attorney general, increasingly into conflict with Coke, the champion of the common law and of the independence of the judges. It was Bacon who examined Coke when the King ordered the judges to be consulted individually and separately in the case of Edmond Peacham, a clergyman charged with treason as the author of an unpublished treatise justifying rebellion against oppression. Bacon has been reprobated for having taken part in the examination under torture of Peacham, which turned out to be fruitless. It was Bacon who instructed Coke and the other judges not to proceed in the case of commendams (i.e., holding of benefices in the absence of the regular incumbent) until they had spoken to the King. Coke’s dismissal in November 1616 for defying this order was quickly followed by Bacon’s appointment as lord keeper of the great seal in March 1617. The following year he was made lord chancellor and baron Verulam, and in 1620/21 he was created viscount St. Albans. The main reason for this progress was his unsparing service in Parliament and the court, together with persistent letters of self-recommendation; according to the traditional account, however, he was also aided by his association with George Villiers, later duke of Buckingham, the King’s new favourite. It would appear that he became honestly fond of Villiers; many of his letters betray a feeling that seems warmer than timeserving flattery. Among Bacon’s papers a notebook has survived, the Commentarius Solutus (“Loose Commentary”), which is revealing. It is a jotting pad “like a Marchant’s wast booke where to enter all maner of remembrance of matter, fourme, business, study, towching my self, service, others, eyther sparsim or in schedules, without any maner of restraint.” This book reveals Bacon reminding himself to flatter a possible patron, to study the weaknesses of a rival, to set intelligent noblemen in the Tower of London to work on serviceable experiments. It displays the multiplicity of his concerns: his income and debts, the King’s business, his own garden and plans for building, philosophical speculations, his health, including his symptoms and medications, and an admonition to learn to control his breathing and not to interrupt in conversation. Between 1608 and 1620 he prepared at least 12 draftings of his most celebrated work, the Novum Organum, and wrote several minor philosophical works. The major occupation of these years must have been the management of James, always with reference, remote or direct, to the royal finances. The King relied on his lord chancellor but did not always follow his advice. Bacon was longer sighted than his contemporaries and seems to have been aware of the constitutional problems that were to culminate in civil war; he dreaded innovation and did all he could, and perhaps more than he should, to safeguard the royal prerogative. Whether his policies were sound or not, it is evident that he was, as he later said, “no mountebank in the King’s services.” Life » Fall from power By 1621 Bacon must have seemed impregnable, a favourite not by charm (though he was witty and had a dry sense of humour) but by sheer usefulness and loyalty to his sovereign; lavish in public expenditure (he was once the sole provider of a court masque); dignified in his affluence and liberal in his household; winning the attention of scholars abroad as the author of the Novum Organum, published in 1620, and the developer of the Instauratio Magna (“Great Instauration”), a comprehensive plan to reorganize the sciences and to restore man to that mastery over nature that he was conceived to have lost by the fall of Adam. But Bacon had his enemies. In 1618 he fell foul of George Villiers when he tried to interfere in the marriage of the daughter of his old enemy, Coke, and the younger brother of Villiers. Then, in 1621, two charges of bribery were raised against him before a committee of grievances over which he himself presided. The shock appears to have been twofold because Bacon, who was casual about the incoming and outgoing of his wealth, was unaware of any vulnerability and was not mindful of the resentment of two men whose cases had gone against them in spite of gifts they had made with the intent of bribing the judge. The blow caught him when he was ill, and he pleaded for extra time to meet the charges, explaining that genuine illness, not cowardice, was the reason for his request. Meanwhile, the House of Lords collected another score of complaints. Bacon admitted the receipt of gifts but denied that they had ever affected his judgment; he made notes on cases and sought an audience with the King that was refused. Unable to defend himself by discriminating between the various charges or cross-examining witnesses, he settled for a penitent submission and resigned the seal of his office, hoping that this would suffice. The sentence was harsh, however, and included a fine of £40,000, imprisonment in the Tower of London during the King’s pleasure, disablement from holding any state office, and exclusion from Parliament and the verge of court (an area of 12 miles radius centred on where the sovereign is resident). Bacon commented to Buckingham: “I acknowledge the sentence just, and for reformation’s sake fit, the justest Chancellor that hath been in the five changes since Sir Nicolas Bacon’s time.” The magnanimity and wit of the epigram sets his case against the prevailing standards. Bacon did not have to stay long in the Tower, but he found the ban that cut him off from access to the library of Charles Cotton, an English man of letters, and from consultation with his physician more galling. He came up against an inimical lord treasurer, and his pension payments were delayed. He lost Buckingham’s goodwill for a time and was put to the humiliating practice of roundabout approaches to other nobles and to Count Gondomar, the Spanish ambassador; remissions came only after vexations and disappointments. Despite all this his courage held, and the last years of his life were spent in work far more valuable to the world than anything he had accomplished in his high office. Cut off from other services, he offered his literary powers to provide the King with a digest of the laws, a history of Great Britain, and biographies of Tudor monarchs. He prepared memorandums on usury and on the prospects of a war with Spain; he expressed views on educational reforms; he even returned, as if by habit, to draft papers of advice to the King or to Buckingham and composed speeches he was never to deliver. Some of these projects were completed, and they did not exhaust his fertility. He wrote: “If I be left to myself I will graze and bear natural philosophy.” Two out of a plan of six separate natural histories were composed—Historia Ventorum (“History of the Winds”) appeared in 1622 and Historia Vitae et Mortis (“History of Life and Death”) in the following year. Also in 1623 he published the De Dignitate et Augmentis Scientiarum, a Latin translation, with many additions, of the Advancement of Learning. He also corresponded with Italian thinkers and urged his works upon them. In 1625 a third and enlarged edition of his Essayes was published. Bacon in adversity showed patience, unimpaired intellectual vigour, and fortitude. Physical deprivation distressed him but what hurt most was the loss of favour; it was not until Jan. 20, 1622/23, that he was admitted to kiss the King’s hand; a full pardon never came. Finally, in March 1626, driving one day near Highgate (a district to the north of London) and deciding on impulse to discover whether snow would delay the process of putrefaction, he stopped his carriage, purchased a hen, and stuffed it with snow. He was seized with a sudden chill, which brought on bronchitis, and he died at the Earl of Arundel’s house nearby on April 9, 1626. Kathleen Marguerite Lea Anthony M. Quinton, Baron Quinton Thought and writings » The intellectual background Bacon appears as an unusually original thinker for several reasons. In the first place he was writing, in the early 17th century, in something of a philosophical vacuum so far as England was concerned. The last great English philosopher, William of Ockham, had died in 1347, two and a half centuries before the Advancement of Learning; the last really important philosopher, John Wycliffe, had died not much later, in 1384. The 15th century had been intellectually cautious and torpid, leavened only by the first small importations of Italian humanism by such cultivated dilettantes as Humphrey Plantagenet, duke of Gloucester, and John Tiptoft, earl of Worcester. The Christian Platonism of the Renaissance became more established at the start of the 16th century in the circle of Erasmus’ English friends: the so-called Oxford Reformers—John Colet, William Grocyn, and Thomas More. But that initiative succumbed to the ecclesiastical frenzies of the age. Philosophy did not revive until Richard Hooker in the 1590s put forward his moderate Anglican version of Thomist rationalism in the form of a theory of the Elizabethan church settlement. This happened a few years before Bacon began to write. In England three systems of thought prevailed in the late 16th century: Aristotelian Scholasticism, scholarly and aesthetic humanism, and occultism. Aristotelian orthodoxy had been reanimated in Roman Catholic Europe after the Council of Trent and the Counter-Reformation had lent authority to the massive output of the 16th-century Spanish theologian and philosopher Francisco Suárez. In England learning remained in general formally Aristotelian, even though some criticism of Aristotle’s logic had reached Cambridge at the time Bacon was a student there in the mid-1570s. But such criticism sought simplicity for the sake of rhetorical effectiveness and not, as Bacon’s critique was to do, in the interests of substantial, practically useful knowledge of nature. The Christian humanist tradition of Petrarch, Lorenzo Valla, and, more recently, of Erasmus was an active force. In contrast to orthodox asceticism, this tradition, in some aspects, inclined to glorify the world and its pleasures and to favour the beauty of art, language, and nature, while remaining comparatively indifferent to religious speculation. Attraction to the beauty of nature, however, if it did not cause was at any rate combined with neglect and disdain for the knowledge of nature. Educationally it fostered the sharp separation between the natural sciences and the humanities that has persisted ever since. Philosophically it was skeptical, nourishing itself, notably in the case of Montaigne, on the rediscovery in 1562 of Sextus Empiricus’ comprehensive survey of the skepticism of Greek thought after Aristotle. The third important current of thought in the world into which Bacon was born was that of occultism, or esotericism, that is, the pursuit of mystical analogies between man and the cosmos, or the search for magical powers over natural processes, as in alchemy and the concoction of elixirs and panaceas. Although its most famous exponent, Paracelsus, was German, occultism was well rooted in England, appealing as it did to the individualistic style of English credulity. Robert Fludd, the leading English occultist, was an approximate contemporary of Bacon. Bacon himself has often been held to have been some kind of occultist, and, even more questionably, to have been a member of the Rosicrucian order, but the sort of “natural magic” he espoused and advertised was altogether different from that of the esoteric philosophers. There was a fourth mode of Renaissance thought outside England to which Bacon’s thinking bore some affinity. Like that of the humanists it was inspired by Plato, at least to some extent, but by another part of his thought, namely its cosmology. This was the boldly systematic nature-philosophy of Nicholas of Cusa and of a number of Italians, in particular Bernardino Telesio, Francesco Patrizzi, Tommaso Campanella, and Giordano Bruno. Nicholas of Cusa and Bruno were highly speculative, but Telesio and, up to a point, Campanella affirmed the primacy of sense perception. In a way that Bacon was later to elaborate formally and systematically, they held knowledge of nature to be a matter of extrapolating from the findings of the senses. There is no allusion to these thinkers in Bacon’s writings. But although he was less metaphysically adventurous than they were, he shared with them the conviction that the human mind is fitted for knowledge of nature and must derive it from observation, not from abstract reasoning. Thought and writings » Bacon’s scheme Bacon drew up an ambitious plan for a comprehensive work that was to appear under the title of Instauratio Magna (“The Great Instauration”), but like many of his literary schemes, it was never completed. Its first part, De Augmentis Scientiarum, appeared in 1623 and is an expanded, Latinized version of his earlier work the Advancement of Learning, published in 1605 (the first really important philosophical book to be written in English). The De Augmentis Scientiarum contains a division of the sciences, a project that had not been embarked on to any great purpose since Aristotle and, in a smaller way, since the Stoics. The second part of Bacon’s scheme, the Novum Organum, which had already appeared in 1620, gives “true directions concerning the interpretation of nature,” in other words, an account of the correct method of acquiring natural knowledge. This is what Bacon believed to be his most important contribution and is the body of ideas with which his name is most closely associated. The fields of possible knowledge having been charted in De Augmentis Scientiarum, the proper method for their cultivation was set out in Novum Organum. Third, there is natural history, the register of matters of observed natural fact, which is the indispensable raw material for the inductive method. Bacon wrote “histories,” in this sense, of the wind, of life and death, and of the dense and the rare, and, near the end of his life, he was working on his Sylva Sylvarum: Or A Natural Historie (“Forest of Forests”), in effect, a collection of collections, a somewhat uncritical miscellany. Fourth, there is the “ladder of the intellect,” consisting of thoroughly worked out examples of the Baconian method in application, the most successful one being the exemplary account in Novum Organum of how his inductive “tables” show heat to be a kind of motion of particles. Fifth, there are the “forerunners,” or pieces of scientific knowledge arrived at by pre-Baconian, common sense methods. Sixth and finally, there is the new philosophy, or science itself, seen by Bacon as a task for later generations armed with his method, advancing into all the regions of possible discovery set out in the Advancement of Learning. The wonder is not so much that Bacon did not complete this immense design but that he got as far with it as he did. Thought and writings » The idols of the mind In the first book of Novum Organum Bacon discusses the causes of human error in the pursuit of knowledge. Aristotle had discussed logical fallacies, commonly found in human reasoning, but Bacon was original in looking behind the forms of reasoning to underlying psychological causes. He invented the metaphor of “idol” to refer to such causes of human error. Bacon distinguishes four idols, or main varieties of proneness to error. The idols of the tribe are certain intellectual faults that are universal to mankind, or, at any rate, very common. One, for example, is a tendency toward oversimplification, that is, toward supposing, for the sake of tidiness, that there exists more order in a field of inquiry than there actually is. Another is a propensity to be overly influenced by particularly sudden or exciting occurrences that are in fact unrepresentative. The idols of the cave are the intellectual peculiarities of individuals. One person may concentrate on the likenesses, another on the differences, between things. One may fasten on detail, another on the totality. The idols of the marketplace are the kinds of error for which language is responsible. It has always been a distinguishing feature of English philosophy to emphasize the unreliable nature of language, which is seen, nominalistically, as a human improvisation. Nominalists argue that even if the power of speech is given by God, it was Adam who named the beasts and thereby gave that power its concrete realization. But language, like other human achievements, partakes of human imperfections. Bacon was particularly concerned with the superficiality of distinctions drawn in everyday language, by which things fundamentally different are classed together (whales and fishes as fish, for example) and things fundamentally similar are distinguished (ice, water, and steam). But he was also concerned, like later critics of language, with the capacity of words to embroil men in the discussion of the meaningless (as, for example, in discussions of the deity Fortune). This aspect of Bacon’s thought has been almost as influential as his account of natural knowledge, inspiring a long tradition of skeptical rationalism, from the Enlightenment to Comtian positivism of the 19th and logical positivism of the 20th centuries. The fourth and final group of idols is that of the idols of the theatre, that is to say mistaken systems of philosophy in the broadest, Baconian sense of the term, in which it embraces all beliefs of any degree of generality. Bacon’s critical polemic in discussing the idols of the theatre is lively but not very penetrating philosophically. He speaks, for example, of the vain affectations of the humanists, but they were not a very apt subject for his criticism. Humanists were really anti-philosophers who not unreasonably turned their attention to nonphilosophical matters because of the apparent inability of philosophers to arrive at conclusions that were either generally agreed upon or useful. Bacon does have something to say about the skeptical philosophy to which humanists appealed when they felt the need for it. Insofar as skepticism involves doubts about deductive reasoning, he has no quarrel with it. Insofar as it is applied not to reason but to the ability of the senses to supply the reason with reliable premises to work from, he brushes it aside too easily. Bacon’s attack on Scholastic orthodoxy is surprisingly rhetorical. It may be that he supposed it to be already sufficiently discredited by its incurably contentious or disputatious character. In his view it was a largely verbal technique for the indefinite prolongation of inconclusive argument by the drawing of artificial distinctions. He has some awareness of the central weakness of Aristotelian science, namely its attempt to derive substantial conclusions from premises that are intuitively evident, and argues that the apparently obvious axioms are neither clear nor indisputable. Perhaps Bacon’s most fruitful disagreement with Scholasticism is his belief that natural knowledge is cumulative, a process of discovery, not of conservation. Living in a time when new worlds were being found on Earth, he was able to free himself from the view that everything men needed to know had already been revealed in the Bible or by Aristotle. Against the fantastic learning of the occultists Bacon argued that individual reports are insufficient, especially since men are emotionally predisposed to credit the interestingly strange. Observations worthy to substantiate theories must be repeatable. Bacon defended the study of nature against those who considered it as either base or dangerous. He argued for a cooperative and methodical procedure and against individualism and intuition. Thought and writings » The classification of the sciences Book II of the Advancement of Learning and Books II to IX of the De Augmentis Scientiarum contain an unprecedentedly thorough and detailed systematization of the whole range of human knowledge. Bacon begins with a distinction of three faculties—memory, imagination, and reason—to which are respectively assigned history, “poesy,” and philosophy. History has an inclusive sense and means all knowledge of singular, individual matters of fact. “Poesy” is “feigned history” and not taken to be cognitive at all and so really irrelevant. After subdividing poesy perfunctorily into narrative, representative (or dramatic), and allusive (or parabolical) forms, Bacon gives it no further consideration. History is divided into natural and civil, the civil category also including ecclesiastical and literary history (which for Bacon is really the history of ideas). History supplies the raw material for philosophy, in other words for the general knowledge that is inductively derived from it. Although Bacon proclaims the universal applicability of induction, he himself treats it almost exclusively as a means to natural knowledge and ignores its civil (or social) application. Two further general distinctions should be mentioned. The first is between the divine and the secular. Most divine knowledge must come from revelation, and reason has nothing to do with it. There is such a thing as divine philosophy (what was later called rational, or natural, theology), but its sole task and competence is to prove that there is a God. The second, more pervasive distinction is between theoretical and practical disciplines, that is, between sciences proper and technologies, or “arts.” Bacon acknowledges something he calls first philosophy, which is secular but not confined to nature or to society. It is concerned with the principles, such as they are, that are common to all the sciences. Natural philosophy divides into natural science as theory on the one hand and the practical discipline of applying natural science’s findings to “the relief of man’s estate” on the other, which he misleadingly describes as natural magic. The former is “the inquisition of causes,” the latter, “the production of effects.” To subdivide still further, natural science is made up of physics and metaphysics, as Bacon understands it. Physics, in his interpretation, is the science of observable correlations; metaphysics is the more theoretical science of the underlying structural factors that explains observable regularities. Each has its practical, or technological, partner; that of physics is mechanics, that of metaphysics, natural magic. It is to the latter that one must look for the real transformation of the human condition through scientific progress. Mechanics is just levers and pulleys. Mathematics is seen by Bacon as an auxiliary to natural science. Many subsequent philosophers of science would agree, understanding it to be a logical means of expressing the content of scientific propositions or of extracting part of that content. But Bacon is not clear about how mathematics was to be of service to science and does not realize that the Galilean physics developing in his own lifetime was entirely mathematical in form. Although one of his three inductive tables is concerned with correlated variations in degree (while the others concern likenesses and differences in kind), he really has no conception of the role, already established in science, of exact numerical measurement. Bacon is fairly cursory about “human philosophy.” Four somewhat quaint sciences of body are sketched—medicine, cosmetic, athletic, and “the voluptuary arts.” The sciences of mind—logic and ethics—are practical, consisting of sets of rules for the correct management of reasoning or conduct, with no suggested theoretical counterpart. Bacon is unreflectively conventional about moral truth, content to rely on the deliverances of the long historical sequence of moralists, undisturbed by their disagreements with one another. Bacon represents civil philosophy in the same uninquiringly practical way. It comprises not only the art of government but also “conversation,” or the art of persuasion, and “negotiation,” or prudence, the topic of proverbs and, to a considerable extent, of his own Essayes. In principle, Bacon is committed to the view that human beings and society are as well fitted for inductive, and, in 20th-century terms, scientific study as the natural world. Yet he depicts human and social studies as the field of nothing more refined than common sense. It was, of course, an achievement to extricate them from religion, and to do so without unnecessary provocation. But in his conception they remain practical arts with no sustaining body of scientific theory to ratify them. It was left to Thomas Hobbes, for a time Bacon’s amanuensis, to develop complete systems of human and social science. Bacon’s practice, however, was better than his program. In his writings on history and law he went beyond the commonplaces of chronicle and precedent and engaged in explanation and theory. Thought and writings » The new method The core of Bacon’s philosophy of science is the account of inductive reasoning given in Book II of Novum Organum. The defect of all previous systems of beliefs about nature, he argued, lay in the inadequate treatment of the general propositions from which the deductions were made. Either they were the result of precipitate generalization from one or two cases, or they were uncritically assumed to be self-evident on the basis of their familiarity and general acceptance. In order to avoid hasty generalization Bacon urges a technique of “gradual ascent,” that is, the patient accumulation of well-founded generalizations of steadily increasing degrees of generality. This method would have the beneficial effect of loosening the hold on men’s minds of ill-constructed everyday concepts that obliterate important differences and fail to register important similarities. The crucial point, Bacon realized, is that induction must work by elimination not, as it does in common life and the defective scientific tradition, by simple enumeration. Thus he stressed “the greater force of the negative instance”—the fact that while “all A are B” is only very weakly confirmed by “this A is B,” it is shown conclusively to be false by “this A is not B.” He devised tables, or formal devices for the presentation of singular pieces of evidence, in order to facilitate the rapid discovery of false generalizations. What survives this eliminative screening, Bacon assumes, may be taken to be true. Bacon presents tables of presence, of absence, and of degree. Tables of presence contain a collection of cases in which one specified property is found. They are then compared to each other to see what other properties are always present. Any property not present in just one case in such a collection cannot be a necessary condition of the property being investigated. Second, there are tables of absence, which list cases that are as alike as possible to the cases in the tables of presence except for the property under investigation. Any property that is found in the second case cannot be a sufficient condition of the original property. Finally, in tables of degree proportionate variations of two properties are compared to see if the proportion is maintained. Bacon rightly showed some hesitation in arriving at the goal he had prescribed for himself, namely constructing a method that would yield general propositions about substantial matters of natural fact that were certain and beyond reasonable doubt. But he hesitated for an insufficient, secondary reason. The application of his tables to a mass of singular evidence, he said, would give only a “first vintage,” a provisional approximation to the truth, because of the defects of natural history, that is to say, the defects inherent in the formulation of the evidence. There are, however, more serious difficulties. An obvious one is that Bacon assumed both that every property natural science can investigate actually has some other property which is both its necessary and sufficient condition (a very strong version of determinism) and also that the conditioning property in each case is readily discoverable. What he had himself laid down as the task of metaphysics in his sense (theoretical natural science in 20th-century terms), namely the discovery of the hidden “forms” that explain what is observed, ensured that the tables could not serve for that task since they are confined to the perceptible accompaniments of what is to be explained. This point is implied by critics who have accused Bacon of failing to recognize the indispensable role of hypotheses in science. In general he adopted a naive and unreflective view about the nature of causes, ignoring their possible complexity and plurality (pointed out by John Stuart Mill) as well as the possibility that they could be at some distance in space and time from their effects. Another weakness, not sufficiently emphasized, is Bacon’s preoccupation with the static. The science that came to glorious maturity in his own century was concerned with change, and, in particular, with motion, as is the natural science of the 20th century. It was with this aspect of the natural world that mathematics, whose role Bacon did not see, came so fruitfully to grips. The conception of a scientific research establishment, which Bacon developed in his utopia, The New Atlantis, may be a more important contribution to science than his theory of induction. Here the idea of science as a collaborative undertaking, conducted in an impersonally methodical fashion and animated by the intention to give material benefits to mankind, is set out with literary force. Thought and writings » Human philosophy Although, as was pointed out above, Bacon’s programmatic account of “human and civic philosophy” (i.e., human and social science) treats it as a matter of practical art, or technique, his own ventures into history and jurisprudence, at any rate, were of a strongly theoretical cast. His Historie of the Raigne of King Henry the Seventh is explanatory, interpretative history, making sense of the King’s policies by tracing them to his cautious, economical, and secretive character. Similarly his reflections on law, in De Augmentis Scientiarum and in Maxims of the Law (Part I of The Elements of the Common Lawes of England), are genuine jurisprudence, not the type of commentary informed by precedent with which most jurists of his time were content. In politics Bacon was as anxious to detach the state from religion as he was to disentangle science from it—both concerns being indicative of very little positive enthusiasm for religion, despite the formal professions of profound respect convention extracted from him. He endorsed the Tudor monarchy and defended it against Coke’s legal obstruction because it was rational and efficient. He had no patience with the inanities of divine right with which James I was infatuated. Bacon wrote little about education, but his memorable assault on the Scholastic obsession with words—an obsession largely carried over, if to different words, by the humanists—bore fruit in the educational theory of Comenius, who acknowledged Bacon’s influence in his argument that children should study actual things as well as books. Thought and writings » Assessment and influence Bacon’s personality has usually been regarded as unattractive: he was cold-hearted, cringed to the powerful, and took bribes, and then had the impudence to say he had not been influenced by them. There is no reason to question this assessment in its fundamentals. It was a hard world for someone in his situation to cut a good figure in, and he did not try to do so. The grimly practical style of his personality is reflected in the particular service he was able to provide of showing a purely secular mind of the highest intellectual power at work. No one who wrote so well could have been insensitive to art. But no one before him had ever quite so uncompromisingly excluded art from the cognitive domain. Bacon was a hero to Robert Hooke and Robert Boyle, founders of the Royal Society. Jean d’Alembert, classifying the sciences in the Encyclopédie, saluted him. Kant, rather surprisingly for one so concerned to limit science in order to make room for faith, dedicated the Critique of Pure Reason to him. He was attacked by Joseph de Maistre for setting man’s miserable reason up against God but glorified by Auguste Comte. It has been suggested that Bacon’s thought received proper recognition only with 19th-century biology, which, unlike mathematical physics, really is Baconian in procedure. Darwin undoubtedly thought so. Bacon’s belief that a new science could contribute to the relief of man’s estate also had to await its time. In the 17th century the chief inventions that flowed from science were of instruments that enabled science to progress further. Today Bacon is best known among philosophers as the symbol of the idea, widely held to be mistaken, that science is inductive. Although there is more to his thought than that, it is, indeed, central; but even if it is wrong, it is as well to have it so boldly and magnificently presented. Anthony M. Quinton, Baron Quinton

Modern philosophy » The rise of empiricism and rationalism » The materialism of Thomas Hobbes

Thomas Hobbes was acquainted with both Bacon and Galileo. With the first he shared a strong concern for philosophical method, with the second an overwhelming interest in matter in motion. His philosophical efforts, however, were more inclusive and more complete than those of his contemporaries. He was a comprehensive thinker within the scope of an exceedingly narrow set of presuppositions, and he produced one of the most systematic philosophies of the early modern period—an almost completely consistent description of humankind, civil society, and nature according to the tenets of mechanistic materialism.

Hobbes’s account of what philosophy is and ought to be clearly distinguished between content and method. As method, philosophy is simply reasoning or calculating by the use of words as to the causes or effects of phenomena. When a person reasons from causes to effects, he reasons synthetically; when he reasons from effects to causes, he reasons analytically. (Hobbes’s strong inclination toward deduction and geometric proofs favoured arguments of the former type.) His dogmatic metaphysical assumption was that physical reality consists entirely of matter in motion. The real world is a corporeal universe in constant movement, and phenomena, or events, the causes and effects of which it is the business of philosophy to lay bare, consist of either the action of physical bodies on each other or the quaint effects of physical bodies upon minds. From this assumption follows Hobbes’s classification of the fields that form the content of philosophy: (1) physics, (2) moral philosophy, and (3) civil philosophy. Physics is the science of the motions and actions of physical bodies conceived in terms of cause and effect. Moral philosophy (or, more accurately, psychology) is the detailed study of “the passions and perturbations of the mind”—that is, how minds are “moved” by desire, aversion, appetite, fear, anger, and envy. And civil philosophy deals with the concerted actions of people in a commonwealth—how, in detail, the wayward wills of human beings can be constrained by power (i.e., force) to prevent civil disorder and maintain peace.

Hobbes’s philosophy was a bold restatement of Greek atomistic materialism, with applications to the realities of early modern politics that would have seemed strange to its ancient authors. But there are also elements in it that make it characteristically English. Hobbes’s account of language led him to adopt nominalism and to deny the reality of universals. Bacon’s general emphasis on experience also had its analogue in Hobbes’s theory that all knowledge arises from sense experiences, all of which are caused by the actions of physical bodies on the sense organs. Empiricism has been a basic and recurrent feature of British intellectual life, and its nominalist and sensationalist roots were already clearly evident in both Bacon and Hobbes.
 

Thomas Hobbes English philosopher born April 5, 1588, Westport, Wiltshire, Eng. died Dec. 4, 1679, Hardwick Hall, Derbyshire Main English philosopher, scientist, and historian, best known for his political philosophy, especially as articulated in his masterpiece Leviathan (1651). Hobbes viewed government primarily as a device for ensuring collective security. Political authority is justified by a hypothetical social contract among the many that vests in a sovereign person or entity the responsibility for the safety and well-being of all. In metaphysics, Hobbes defended materialism, the view that only material things are real. His scientific writings present all observed phenomena as the effects of matter in motion. Hobbes was not only a scientist in his own right but a great systematizer of the scientific findings of his contemporaries, including Galileo and Johannes Kepler. His enduring contribution is as a political philosopher who justified wide-ranging government powers on the basis of the self-interested consent of citizens. Early life Hobbes’s father was a quick-tempered vicar of a small Wiltshire parish church. Disgraced after engaging in a brawl at his own church door, he disappeared and abandoned his three children to the care of his brother, a well-to-do glover in Malmesbury. When he was four years old, Hobbes was sent to school at Westport, then to a private school, and finally, at 15, to Magdalen Hall in the University of Oxford, where he took a traditional arts degree and in his spare time developed an interest in maps. For nearly the whole of his adult life, Hobbes worked for different branches of the wealthy and aristocratic Cavendish family. Upon taking his degree at Oxford in 1608, he was employed as page and tutor to the young William Cavendish, afterward the second earl of Devonshire. Over the course of many decades Hobbes served the family and their associates as translator, traveling companion, keeper of accounts, business representative, political adviser, and scientific collaborator. Through his employment by William Cavendish, the first earl of Devonshire, and his heirs, Hobbes became connected with the royalist side in disputes between the king and Parliament that continued until the 1640s and that culminated in the English Civil Wars (1642–51). Hobbes also worked for the marquess of Newcastle-upon-Tyne, a cousin of William Cavendish, and Newcastle’s brother, Sir Charles Cavendish. The latter was the centre of the “Wellbeck Academy,” an informal network of scientists named for one of the family houses at Wellbeck Abbey in Nottinghamshire. Intellectual development The two branches of the Cavendish family nourished Hobbes’s enduring intellectual interests in politics and natural science, respectively. Hobbes served the earls of Devonshire intermittently until 1628; Newcastle and his brother employed him in the following decade. He returned to the Devonshires after the 1640s. Through both branches of the Cavendish family, and through contacts he made in his own right on the Continent as traveling companion to various successors to the Devonshire title, Hobbes became a member of several networks of intellectuals in England. Farther afield, in Paris, he became acquainted with the circle of scientists, theologians, and philosophers presided over by the theologian Marin Mersenne. This circle included René Descartes. Hobbes was exposed to practical politics before he became a student of political philosophy. The young William Cavendish was a member of the 1614 and 1621 Parliaments, and Hobbes would have followed his contributions to parliamentary debates. Further exposure to politics came through the commercial interests of the earls of Devonshire. Hobbes attended many meetings of the governing body of the Virginia Company, a trading company established by James I to colonize parts of the eastern coast of North America, and came into contact with powerful men there. (Hobbes himself was given a small share in the company by his employer.) He also confronted political issues through his connection with figures who met at Great Tew; with them he debated not only theological questions but also the issues of how the Anglican church should be led and organized and how its authority should be related to that of any English civil government. In the late 1630s Parliament and the king were in conflict over how far normal kingly powers could be exceeded in exceptional circumstances, especially in regard to raising money for armies. In 1640 Hobbes wrote a treatise defending King Charles I’s own wide interpretation of his prerogatives. Royalist members of Parliament used arguments from Hobbes’s treatise in debates, and the treatise itself circulated in manuscript form. The Elements of Law, Natural and Politic (written in 1640, published in a misedited unauthorized version in 1650) was Hobbes’s first work of political philosophy, though he did not intend it for publication as a book. The development of Hobbes the scientist began in his middle age. He was not trained in mathematics or the sciences at Oxford, and his Wiltshire schooling was strongest in classical languages. His interest in motion and its effects was stimulated mainly through his conversation and reading on the Continent, as well as through his association with the scientifically and mathematically minded Wellbeck Cavendishes. In 1629 or 1630 Hobbes was supposedly charmed by Euclid’s method of demonstrating theorems in the Elements. According to a contemporary biographer, he came upon a volume of Euclid in a gentleman’s study and fell in love with geometry. Later, perhaps in the mid-1630s, he had gained enough sophistication to pursue independent research in optics, a subject he later claimed to have pioneered. Within the Wellbeck Academy, he exchanged views with other people interested in the subject. And as a member of Mersenne’s circle in Paris after 1640, he was taken seriously as a theorist not only of ethics and politics but of optics and ballistics. Indeed, he was even credited with competence in mathematics by some very able French mathematicians, including Gilles Personne de Roberval. Self-taught in the sciences and an innovator at least in optics, Hobbes also regarded himself as a teacher or transmitter of sciences developed by others. In this connection he had in mind sciences that, like his own optics, traced observed phenomena to principles about the sizes, shapes, positions, speeds, and paths of parts of matter. His great trilogy—De Corpore (1655; “Concerning Body”), De Homine (1658; “Concerning Man”), and De Cive (1642; “Concerning the Citizen”)—was his attempt to arrange the various pieces of natural science, as well as psychology and politics, into a hierarchy, ranging from the most general and fundamental to the most specific. Although logically constituting the last part of his system, De Cive was published first, because political turmoil in England made its message particularly timely and because its doctrine was intelligible both with and without natural-scientific preliminaries. De Corpore and De Homine incorporated the findings of, among others, Galileo on the motions of terrestrial bodies, Kepler on astronomy, William Harvey on the circulation of the blood, and Hobbes himself on optics. The science of politics contained in De Cive was substantially anticipated in Part II of The Elements of Law and further developed in Leviathan; or, The Matter, Form, and Power of a Commonwealth, Ecclesiastical and Civil (1651), the last—and in the English-speaking world the most famous—formulation of Hobbes’s political philosophy (see below Hobbes’s system). Exile in Paris When strife became acute in 1640, Hobbes feared for his safety. Shortly after completing The Elements of Law, he fled to Paris, where he rejoined Mersenne’s circle and made contact with other exiles from England. He would remain in Paris for more than a decade, working on optics and on De Cive, De Corpore, and Leviathan. In 1646 the young prince of Wales, later to become Charles II, sought refuge in Paris, and Hobbes accepted an invitation to instruct him in mathematics. Political philosophy Hobbes presented his political philosophy in different forms for different audiences. De Cive states his theory in what he regarded as its most scientific form. Unlike The Elements of Law, which was composed in English for English parliamentarians—and which was written with local political challenges to Charles I in mind—De Cive was a Latin work for an audience of Continental savants who were interested in the “new” science—that is, the sort of science that did not appeal to the authority of the ancients but approached various problems with fresh principles of explanation. De Cive’s break from the ancient authority par excellence—Aristotle—could not have been more loudly advertised. After only a few paragraphs, Hobbes rejects one of the most famous theses of Aristotle’s politics, namely that human beings are naturally suited to life in a polis and do not fully realize their natures until they exercise the role of citizen. Hobbes turns Aristotle’s claim on its head: human beings, he insists, are by nature unsuited to political life. They naturally denigrate and compete with each other, are very easily swayed by the rhetoric of ambitious men, and think much more highly of themselves than of other people. In short, their passions magnify the value they place on their own interests, especially their near-term interests. At the same time, most people, in pursuing their own interests, do not have the ability to prevail over competitors. Nor can they appeal to some natural common standard of behaviour that everyone will feel obliged to abide by. There is no natural self-restraint, even when human beings are moderate in their appetites, for a ruthless and bloodthirsty few can make even the moderate feel forced to take violent preemptive action in order to avoid losing everything. The self-restraint even of the moderate, then, easily turns into aggression. In other words, no human being is above aggression and the anarchy that goes with it. War comes more naturally to human beings than political order. Indeed, political order is possible only when human beings abandon their natural condition of judging and pursuing what seems best to each and delegate this judgment to someone else. This delegation is effected when the many contract together to submit to a sovereign in return for physical safety and a modicum of well-being. Each of the many in effect says to the other: “I transfer my right of governing myself to X (the sovereign) if you do too.” And the transfer is collectively entered into only on the understanding that it makes one less of a target of attack or dispossession than one would be in one’s natural state. Although Hobbes did not assume that there was ever a real historical event in which a mutual promise was made to delegate self-government to a sovereign, he claimed that the best way to understand the state was to conceive of it as having resulted from such an agreement. In Hobbes’s social contract, the many trade liberty for safety. Liberty, with its standing invitation to local conflict and finally all-out war—a “war of every man against every man”—is overvalued in traditional political philosophy and popular opinion, according to Hobbes; it is better for people to transfer the right of governing themselves to the sovereign. Once transferred, however, this right of government is absolute, unless the many feel that their lives are threatened by submission. The sovereign determines who owns what, who will hold which public offices, how the economy will be regulated, what acts will be crimes, and what punishments criminals should receive. The sovereign is the supreme commander of the army, supreme interpreter of law, and supreme interpreter of scripture, with authority over any national church. It is unjust—a case of reneging on what one has agreed—for any subject to take issue with these arrangements, for, in the act of creating the state or by receiving its protection, one agrees to leave judgments about the means of collective well-being and security to the sovereign. The sovereign’s laws and decrees and appointments to public office may be unpopular; they may even be wrong. But unless the sovereign fails so utterly that subjects feel that their condition would be no worse in the free-for-all outside the state, it is better for the subjects to endure the sovereign’s rule. It is better both prudentially and morally. Because no one can prudently welcome a greater risk of death, no one can prudently prefer total liberty to submission. Total liberty invites war, and submission is the best insurance against war. Morality too supports this conclusion, for, according to Hobbes, all the moral precepts enjoining virtuous behaviour can be understood as derivable from the fundamental moral precept that one should seek peace—that is to say, freedom from war—if it is safe to do so. Without peace, he observed, man lives in “continual fear, and danger of violent death,” and what life he has is “solitary, poor, nasty, brutish, and short.” What Hobbes calls the “laws of nature,” the system of moral rules by which everyone is bound, cannot be safely complied with outside the state, for the total liberty that people have outside the state includes the liberty to flout the moral requirements if one’s survival seems to depend on it. The sovereign is not a party to the social contract; he receives the obedience of the many as a free gift in their hope that he will see to their safety. The sovereign makes no promises to the many in order to win their submission. Indeed, because he does not transfer his right of self-government to anyone, he retains the total liberty that his subjects trade for safety. He is not bound by law, including his own laws. Nor does he do anything unjustly if he makes decisions about his subjects’s safety and well-being that they do not like. Although the sovereign is in a position to judge the means of survival and well-being for the many more dispassionately than they are able to do themselves, he is not immune to self-interested passions. Hobbes realizes that the sovereign may behave iniquitously. He insists that it is very imprudent for a sovereign to act so iniquitously that he disappoints his subjects’s expectation of safety and makes them feel insecure. Subjects who are in fear of their lives lose their obligations to obey and, with that, deprive the sovereign of his power. Reduced to the status of one among many by the defection of his subjects, the unseated sovereign is likely to feel the wrath of those who submitted to him in vain. Hobbes’s masterpiece, Leviathan (1651), does not significantly depart from the view of De Cive concerning the relation between protection and obedience, but it devotes much more attention to the civil obligations of Christian believers and the proper and improper roles of a church within a state. Hobbes argues that believers do not endanger their prospects of salvation by obeying a sovereign’s decrees to the letter, and he maintains that churches do not have any authority that is not granted by the civil sovereign. Hobbes’s political views exerted a discernible influence on his work in other fields, including historiography and legal theory. His political philosophy is chiefly concerned with the way in which government must be organized in order to avoid civil war. It therefore encompasses a view of the typical causes of civil war, all of which are represented in Behemoth; or, The Long Parliament (1679), his history of the English Civil Wars. Hobbes produced the first English translation of Thucydides’ History of the Pelopponesian War, which he thought contained important lessons for his contemporaries regarding the excesses of democracy, the worst kind of dilution of sovereign authority, in his view. Hobbes’s works on church history and the history of philosophy also strongly reflect his politics. He was firmly against the separation of government powers, either between branches of government or between church and state. His ecclesiastical history emphasizes the way in which power-hungry priests and popes threatened legitimate civil authority. His history of philosophy is mostly concerned with how metaphysics was used as a means of keeping people under the sway of Roman Catholicism at the expense of obedience to a civil authority. His theory of law develops a similar theme regarding the threats to a supreme civil power posed by common law and the multiplication of authoritative legal interpreters. Return to England There are signs that Hobbes intended Leviathan to be read by a monarch, who would be able to take the rules of statecraft from it. A specially bound copy was given to Prince Charles while he was in exile in Paris. Unfortunately, Hobbes’s suggestion in Leviathan that a subject had the right to abandon a ruler who could no longer protect him gave serious offense to the prince’s advisers. Barred from the exiled court and under suspicion by the French authorities for his attack on the papacy (see below), Hobbes found his position in Paris becoming daily more intolerable. At the end of 1651, at about the time that Leviathan was published, he returned to England and made his peace with the new regime of Oliver Cromwell. Hobbes submitted to that authority for a long time before the monarchy was restored in 1660. From the time of the Restoration in 1660, Hobbes enjoyed a new prominence. Charles II received Hobbes again into favour. Although Hobbes’s presence at court scandalized the bishops and the chancellor, the king relished his wit. He even granted Hobbes a pension of £100 a year and had his portrait hung in the royal closet. It was not until 1666, when the House of Commons prepared a bill against atheism and profaneness, that Hobbes felt seriously endangered, for the committee to which the bill was referred was instructed to investigate Leviathan. Hobbes, then verging upon 80, burned such of his papers as he thought might compromise him. Optics Hobbes’s most significant contributions to natural science were in the field of optics. An optical theory in his day was expected to pronounce on the nature of light, on the transmission of light from the Sun to the Earth, on reflection and refraction, and on the workings of optical instruments such as mirrors and lenses. Hobbes took up these topics in several relatively short treatises and in correspondence, including with Descartes on the latter’s Dioptrics (1637). The most polished of Hobbes’s optical works was A Minute or First Draught of the Optiques (1646). In its mature form, Hobbes’s optical theory held that the dilations and contractions of an original light source, such as the Sun, are transmitted by contact with a uniform, pervading ethereal medium, which in turn stimulates the eye and the nerves connected to it, eventually resulting in a “phantasm,” or sense-image, in the brain. In Hobbes’s theory, the qualities of a sense-image do not need to be explained in terms of the qualities of a perceived object. Instead, motion and matter—the motion of a light source, the disturbance of a physical nervous system, and sensory membranes—are all that have to be invoked. In contrast, traditional optics—optics as developed within Aristotle’s framework—had held that seeing the colour of something—the redness of a strawberry, for example—was a matter of reproducing the “form” of the colour in the sense organs; the form is then abstracted from the sense organs by the mind. “Sensible forms,” the characteristic properties transmitted by objects to the senses in the act of perception, were entirely dispensed with in Hobbes’s optics. Hobbes’s system Theories that trace all observed effects to matter and motion are called mechanical. Hobbes was thus a mechanical materialist: He held that nothing but material things are real, and he thought that the subject matter of all the natural sciences consists of the motions of material things at different levels of generality. Geometry considers the effects of the motions of points, lines, and solids; pure mechanics deals with the motions of three-dimensional bodies in a full space, or plenum; physics deals with the motions of the parts of inanimate bodies insofar as they contribute to observed phenomena; and psychology deals with the effects of the internal motions of animate bodies on behaviour. The system of the natural sciences described in Hobbes’s trilogy represents his understanding of the materialist principles on which all science is based. The fact that Hobbes included politics as well as psychology within his system, however, has tended to overshadow his insistence on the autonomy of political understanding from natural-scientific understanding. According to Hobbes, politics does not need to be understood in terms of the motions of material things (although, ultimately, it can be); a certain kind of widely available self-knowledge is evidence enough of the human propensity to war. Although Hobbes is routinely read as having discerned the “laws of motion” for both human beings and human societies, the most that can plausibly be claimed is that he based his political philosophy on psychological principles that he thought could be illuminated by general laws of motion. Last years and influence Although he was impugned by enemies at home, no Englishman of the day stood in such high repute abroad as Hobbes, and distinguished foreigners who visited England were always eager to pay their respects to the old man, whose vigour and freshness of intellect remained unquenched. In his last years Hobbes amused himself by returning to the classical studies of his youth. The autobiography in Latin verse with its playful humour, occasional pathos, and sublime self-complacency was brought forth at the age of 84. In 1675 he produced a translation of the Odyssey in rugged English rhymes, with a lively preface, “Concerning the Virtues of an Heroic Poem.” A translation of the Iliad appeared in the following year. As late as four months before his death, he was promising his publisher “somewhat to print in English.” Hobbes’s importance lies not only in his political philosophy but also in his contribution to the development of an anti-Aristotelian and thoroughly materialist conception of natural science. His political philosophy influenced not only successors who adopted the social-contract framework—John Locke, Jean-Jacques Rousseau, and Immanuel Kant, for example—but also less directly those theorists who connected moral and political decision making in rational human beings to considerations of self-interest broadly understood. The materialist bent of Hobbes’s metaphysics is also much in keeping with contemporary Anglo-American, or analytic, metaphysics, which tends to recognize as real only those entities that physics in particular or natural science in general presupposes. Tom Sorell

Modern philosophy » The rise of empiricism and rationalism » The rationalism of Descartes

The dominant philosophy of the last half of the 17th century was that of René Descartes. A crucial figure in the history of philosophy, Descartes combined (however unconsciously or even unwillingly) the influences of the past into a synthesis that was striking in its originality and yet congenial to the scientific temper of the age. In the minds of all later historians, he counts as the progenitor of the modern spirit of philosophy.

From the past there seeped into the Cartesian synthesis doctrines about God from Anselm and Aquinas, a theory of the will from Augustine, a deep sympathy with the Stoicism of the Romans, and a skeptical method taken indirectly from Pyrrho and Sextus Empiricus. But Descartes was also a great mathematician—he invented analytic geometry—and the author of many important physical and anatomical experiments. He knew and profoundly respected the work of Galileo; indeed, he withdrew from publication his own cosmological treatise, The World, after Galileo’s condemnation by the Inquisition in 1633.

Each of the maxims of Leonardo, which constitute the Renaissance worldview, found its place in Descartes: empiricism in the physiological researches described in the Discourse on Method (1637), a mechanistic interpretation of the physical world and of human action in the Principles of Philosophy (1644) and The Passions of the Soul (1649), and a mathematical bias that dominates the theory of method in Rules for the Direction of the Mind (1701) and the metaphysics of the Meditations on the First Philosophy (1642). But it is the mathematical theme that clearly predominates in Descartes’s philosophy.

Bacon and Descartes, the founders of modern empiricism and rationalism, respectively, both subscribed to two pervasive tenets of the Renaissance: an enormous enthusiasm for physical science and the belief that knowledge means power—that the ultimate purpose of theoretical science is to serve the practical needs of human beings.

In his Principles, Descartes defined philosophy as “the study of wisdom” or “the perfect knowledge of all one can know.” Its chief utility is “for the conduct of life” (morals), “the conservation of health” (medicine), and “the invention of all the arts” (mechanics). He expressed the relation of philosophy to practical endeavours in the famous metaphor of the “tree”: the roots are metaphysics, the trunk is physics, and the branches are morals, medicine, and mechanics. The metaphor is revealing, for it indicates that for Descartes—as for Bacon and Galileo—the most important part of the tree was the trunk. In other words, Descartes busied himself with metaphysics only in order to provide a firm foundation for physics. Thus, the Discourse on Method, which provides a synoptic view of the Cartesian philosophy, shows it to be not a metaphysics founded upon physics (as was the case with Aristotle) but rather a physics founded upon metaphysics.

Descartes’s mathematical bias was reflected in his determination to ground natural science not in sensation and probability (as did Bacon) but in premises that could be known with absolute certainty. Thus his metaphysics in essence consisted of three principles:

1. To employ the procedure of complete and systematic doubt to eliminate every belief that does not pass the test of indubitability (skepticism).

2. To accept no idea as certain that is not clear, distinct, and free of contradiction (mathematicism).

3. To found all knowledge upon the bedrock certainty of self-consciousness, so that “I think, therefore I am” becomes the only innate idea unshakable by doubt (subjectivism).

From the indubitability of the self, Descartes inferred the existence of a perfect God; and, from the fact that a perfect being is incapable of falsification or deception, he concluded that the ideas about the physical world that God has implanted in human beings must be true. The achievement of certainty about the natural world was thus guaranteed by the perfection of God and by the “clear and distinct” ideas that are his gift.

Cartesian metaphysics is the fountainhead of rationalism in modern philosophy, for it suggests that the mathematical criteria of clarity, distinctness, and logical consistency are the ultimate test of meaningfulness and truth. This stance is profoundly antiempirical. Bacon, who remarked that “reasoners resemble spiders who make cobwebs out of their own substance,” might well have said the same of Descartes, for the Cartesian self is just such a substance. Yet for Descartes the understanding is vastly superior to the senses, and only reason can ultimately decide what constitutes truth in science.

Cartesianism dominated the intellectual life of continental Europe until the end of the 17th century. It was a fashionable philosophy, appealing to learned gentlemen and highborn ladies alike, and it was one of the few philosophical alternatives to the Scholasticism still being taught in the universities. Precisely for this reason it constituted a serious threat to established religious authority. In 1663 the Roman Catholic Church placed Descartes’s works on the Index Librorum Prohibitorum (“Index of Forbidden Books”), and the University of Oxford forbade the teaching of his doctrines. Only in the liberal Dutch universities, such as those of Groningen and Utrecht, did Cartesianism make serious headway.

Certain features of Cartesian philosophy made it an important starting point for subsequent philosophical speculation. As a kind of meeting point for medieval and modern worldviews, it accepted the doctrines of Renaissance science while attempting to ground them metaphysically in medieval notions of God and the human mind. Thus, a certain dualism between God the Creator and the mechanistic world of his creation, between mind as a spiritual principle and matter as mere spatial extension, was inherent in the Cartesian position. An entire generation of Cartesians—among them Arnold Geulincx, Nicolas Malebranche, and Pierre Bayle—wrestled with the resulting problem of how interaction between two such radically different entities is possible.
 

René Descartes French mathematician and philosopher born March 31, 1596, La Haye, Touraine, France died February 11, 1650, Stockholm, Sweden Main French mathematician, scientist, and philosopher. Because he was one of the first to abandon scholastic Aristotelianism, because he formulated the first modern version of mind-body dualism, from which stems the mind-body problem, and because he promoted the development of a new science grounded in observation and experiment, he has been called the father of modern philosophy. Applying an original system of methodical doubt, he dismissed apparent knowledge derived from authority, the senses, and reason and erected new epistemic foundations on the basis of the intuition that, when he is thinking, he exists; this he expressed in the dictum “I think, therefore I am” (best known in its Latin formulation, “Cogito, ergo sum,” though originally written in French, “Je pense, donc je suis”). He developed a metaphysical dualism that distinguishes radically between mind, the essence of which is thinking, and matter, the essence of which is extension in three dimensions. Descartes’s metaphysics is rationalist, based on the postulation of innate ideas of mind, matter, and God, but his physics and physiology, based on sensory experience, are mechanistic and empiricist. Early life and education Although Descartes’s birthplace, La Haye (now Descartes), France, is in Touraine, his family connections lie south, across the Creuse River in Poitou, where his father, Joachim, owned farms and houses in Châtellerault and Poitiers. Because Joachim was a councillor in the Parlement of Brittany in Rennes, Descartes inherited a modest rank of nobility. Descartes’s mother died when he was one year old. His father remarried in Rennes, leaving him in La Haye to be raised first by his maternal grandmother and then by his great-uncle in Châtellerault. Although the Descartes family was Roman Catholic, the Poitou region was controlled by the Protestant Huguenots, and Châtellerault, a Protestant stronghold, was the site of negotiations over the Edict of Nantes (1598), which gave Protestants freedom of worship in France following the intermittent Wars of Religion between Protestant and Catholic forces in France. Descartes returned to Poitou regularly until 1628. In 1606 Descartes was sent to the Jesuit college at La Flèche, established in 1604 by Henry IV (reigned 1589–1610). At La Flèche, 1,200 young men were trained for careers in military engineering, the judiciary, and government administration. In addition to classical studies, science, mathematics, and metaphysics—Aristotle was taught from scholastic commentaries—they studied acting, music, poetry, dancing, riding, and fencing. In 1610 Descartes participated in an imposing ceremony in which the heart of Henry IV, whose assassination that year had destroyed the hope of religious tolerance in France and Germany, was placed in the cathedral at La Flèche. In 1614 Descartes went to Poitiers, where he took a law degree in 1616. At this time, Huguenot Poitiers was in virtual revolt against the young King Louis XIII (reigned 1610–43). Descartes’s father probably expected him to enter Parlement, but the minimum age for doing so was 27, and Descartes was only 20. In 1618 he went to Breda in the Netherlands, where he spent 15 months as an informal student of mathematics and military architecture in the peacetime army of the Protestant stadholder, Prince Maurice (ruled 1585–1625). In Breda, Descartes was encouraged in his studies of science and mathematics by the physicist Isaac Beeckman (1588–1637), for whom he wrote the Compendium of Music (written 1618, published 1650), his first surviving work. Descartes spent the period 1619 to 1628 traveling in northern and southern Europe, where, as he later explained, he studied “the book of the world.” While in Bohemia in 1619, he invented analytic geometry, a method of solving geometric problems algebraically and algebraic problems geometrically. He also devised a universal method of deductive reasoning, based on mathematics, that is applicable to all the sciences. This method, which he later formulated in Discourse on Method (1637) and Rules for the Direction of the Mind (written by 1628 but not published until 1701), consists of four rules: (1) accept nothing as true that is not self-evident, (2) divide problems into their simplest parts, (3) solve problems by proceeding from simple to complex, and (4) recheck the reasoning. These rules are a direct application of mathematical procedures. In addition, Descartes insisted that all key notions and the limits of each problem must be clearly defined. Descartes also investigated reports of esoteric knowledge, such as the claims of the practitioners of theosophy to be able to command nature. Although disappointed with the followers of the Catalan mystic Ramon Llull (1232/33–1315/16) and the German alchemist Heinrich Cornelius Agrippa von Nettesheim (1486–1535), he was impressed by the German mathematician Johann Faulhaber (1580–1635), a member of the mystical society of the Rosicrucians. Descartes shared a number of Rosicrucian goals and habits. Like the Rosicrucians, he lived alone and in seclusion, changed his residence often (during his 22 years in the Netherlands, he lived in 18 different places), practiced medicine without charge, attempted to increase human longevity, and took an optimistic view of the capacity of science to improve the human condition. At the end of his life, he left a chest of personal papers (none of which has survived) with a Rosicrucian physician—his close friend Corneille van Hogelande, who handled his affairs in the Netherlands. Despite these affinities, Descartes rejected the Rosicrucians’ magical and mystical beliefs. For him, this period was a time of hope for a revolution in science. The English philosopher Francis Bacon (1561–1626), in Advancement of Learning (1605), had earlier proposed a new science of observation and experiment to replace the traditional Aristotelian science, as Descartes himself did later. In 1622 Descartes moved to Paris. There he gambled, rode, fenced, and went to the court, concerts, and the theatre. Among his friends were the poets Jean-Louis Guez de Balzac (1597–1654), who dedicated his Le Socrate chrétien (1652; “Christian Socrates”) to Descartes, and Théophile de Viau (1590–1626), who was burned in effigy and imprisoned in 1623 for writing verses mocking religious themes. Descartes also befriended the mathematician Claude Mydorge (1585–1647) and Father Marin Mersenne (1588–1648), a man of universal learning who corresponded with hundreds of scholars, writers, mathematicians, and scientists and who became Descartes’s main contact with the larger intellectual world. During this time Descartes regularly hid from his friends to work, writing treatises, now lost, on fencing and metals. He acquired a considerable reputation long before he published anything. At a talk in 1628, Descartes denied the alchemist Chandoux’s claim that probabilities are as good as certainties in science and demonstrated his own method for attaining certainty. The Cardinal Pierre de Bérulle (1575–1629)—who had founded the Oratorian teaching congregation in 1611 as a rival to the Jesuits—was present at the talk. Many commentators speculate that Bérulle urged Descartes to write a metaphysics based on the philosophy of St. Augustine as a replacement for Jesuit teaching. Be that as it may, within weeks Descartes left for the Netherlands, which was Protestant, and—taking great precautions to conceal his address—did not return to France for 16 years. Some scholars claim that Descartes adopted Bérulle as director of his conscience, but this is unlikely, given Descartes’s background and beliefs (he came from a Huguenot province, he was not a Catholic enthusiast, he had been accused of being a Rosicrucian, and he advocated religious tolerance and championed the use of reason). Residence in the Netherlands Descartes said that he went to the Netherlands to enjoy a greater liberty than was available anywhere else and to avoid the distractions of Paris and friends so that he could have the leisure and solitude to think. (He had inherited enough money and property to live independently.) The Netherlands was a haven of tolerance, where Descartes could be an original, independent thinker without fear of being burned at the stake—as was the Italian philosopher Lucilio Vanini (1585–1619) for proposing natural explanations of miracles—or being drafted into the armies then prosecuting the Catholic Counter-Reformation. In France, by contrast, religious intolerance was mounting. The Jews were expelled in 1615, and the last Protestant stronghold, La Rochelle, was crushed—with Bérulle’s participation—only weeks before Descartes’s departure. In 1624 the French Parlement passed a decree forbidding criticism of Aristotle on pain of death. Although Mersenne and the philosopher Pierre Gassendi (1592–1655) did publish attacks on Aristotle without suffering persecution (they were, after all, Catholic priests), those judged to be heretics continued to be burned, and laymen lacked church protection. In addition, Descartes may have felt jeopardized by his friendship with intellectual libertines such as Father Claude Picot (d. 1668), a bon vivant known as “the Atheist Priest,” with whom he entrusted his financial affairs in France. In 1629 Descartes went to the university at Franeker, where he stayed with a Catholic family and wrote the first draft of his Meditations. He matriculated at the University of Leiden in 1630. In 1631 he visited Denmark with the physician and alchemist Étienne de Villebressieu, who invented siege engines, a portable bridge, and a two-wheeled stretcher. The physician Henri Regius (1598–1679), who taught Descartes’s views at the University of Utrecht in 1639, involved Descartes in a fierce controversy with the Calvinist theologian Gisbertus Voetius (1589–1676) that continued for the rest of Descartes’s life. In his Letter to Voetius of 1648, Descartes made a plea for religious tolerance and the rights of man. Claiming to write not only for Christians but also for Turks—meaning Muslims, libertines, infidels, deists, and atheists—he argued that, because Protestants and Catholics worship the same God, both can hope for heaven. When the controversy became intense, however, Descartes sought the protection of the French ambassador and of his friend Constantijn Huygens (1596–1687), secretary to the stadholder Prince Frederick Henry (ruled 1625–47). In 1635 Descartes’s daughter Francine was born to Helena Jans and was baptized in the Reformed Church in Deventer. Although Francine is typically referred to by commentators as Descartes’s “illegitimate” daughter, her baptism is recorded in a register for legitimate births. Her death of scarlet fever at the age of five was the greatest sorrow of Descartes’s life. Referring to her death, Descartes said that he did not believe that one must refrain from tears to prove oneself a man. The World and Discourse on Method In 1633, just as he was about to publish The World (1664), Descartes learned that the Italian astronomer Galileo Galilei (1564–1642) had been condemned in Rome for publishing the view that the Earth revolves around the Sun. Because this Copernican position is central to his cosmology and physics, Descartes suppressed The World, hoping that eventually the church would retract its condemnation. Although Descartes feared the church, he also hoped that his physics would one day replace that of Aristotle in church doctrine and be taught in Catholic schools. Descartes’s Discourse on Method (1637) is one of the first important modern philosophical works not written in Latin. Descartes said that he wrote in French so that all who had good sense, including women, could read his work and learn to think for themselves. He believed that everyone could tell true from false by the natural light of reason. In three essays accompanying the Discourse, he illustrated his method for utilizing reason in the search for truth in the sciences: in Dioptrics he derived the law of refraction, in Meteorology he explained the rainbow, and in Geometry he gave an exposition of his analytic geometry. He also perfected the system invented by François Viète for representing known numerical quantities with a, b, c, … , unknowns with x, y, z, … , and squares, cubes, and other powers with numerical superscripts, as in x2, x3, … , which made algebraic calculations much easier than they had been before. In the Discourse he also provided a provisional moral code (later presented as final) for use while seeking truth: (1) obey local customs and laws, (2) make decisions on the best evidence and then stick to them firmly as though they were certain, (3) change desires rather than the world, and (4) always seek truth. This code exhibits Descartes’s prudential conservatism, decisiveness, stoicism, and dedication. The Discourse and other works illustrate Descartes’s conception of knowledge as being like a tree in its interconnectedness and in the grounding provided to higher forms of knowledge by lower or more fundamental ones. Thus, for Descartes, metaphysics corresponds to the roots of the tree, physics to the trunk, and medicine, mechanics, and morals to the branches. Meditations In 1641 Descartes published the Meditations on First Philosophy, in Which Is Proved the Existence of God and the Immortality of the Soul. Written in Latin and dedicated to the Jesuit professors at the Sorbonne in Paris, the work includes critical responses by several eminent thinkers—collected by Mersenne from the Jansenist philosopher and theologian Antoine Arnauld (1612–94), the English philosopher Thomas Hobbes (1588–1679), and the Epicurean atomist Pierre Gassendi (1592–1655)—as well as Descartes’s replies. The second edition (1642) includes a response by the Jesuit priest Pierre Bourdin (1595–1653), who Descartes said was a fool. These objections and replies constitute a landmark of cooperative discussion in philosophy and science at a time when dogmatism was the rule. The Meditations is characterized by Descartes’s use of methodic doubt, a systematic procedure of rejecting as though false all types of belief in which one has ever been, or could ever be, deceived. His arguments derive from the skepticism of the Greek philosopher Sextus Empiricus (fl. 3rd century ad) as reflected in the work of the essayist Michel de Montaigne (1533–92) and the Catholic theologian Pierre Charron (1541–1603). Thus, Descartes’s apparent knowledge based on authority is set aside, because even experts are sometimes wrong. His beliefs from sensory experience are declared untrustworthy, because such experience is sometimes misleading, as when a square tower appears round from a distance. Even his beliefs about the objects in his immediate vicinity may be mistaken, because, as he notes, he often has dreams about objects that do not exist, and he has no way of knowing with certainty whether he is dreaming or awake. Finally, his apparent knowledge of simple and general truths of reasoning that do not depend on sense experience—such as “2 + 3 = 5” or “a square has four sides”—is also unreliable, because God could have made him in such a way that, for example, he goes wrong every time he counts. As a way of summarizing the universal doubt into which he has fallen, Descartes supposes that an “evil genius of the utmost power and cunning has employed all his energies in order to deceive me.” Although at this stage there is seemingly no belief about which he cannot entertain doubt, Descartes finds certainty in the intuition that, when he is thinking—even if he is being deceived—he must exist. In the Discourse, Descartes expresses this intuition in the dictum “I think, therefore I am”; but because “therefore” suggests that the intuition is an argument—though it is not—in the Meditations he says merely, “I think, I am” (“Cogito, sum”). The cogito is a logically self-evident truth that also gives intuitively certain knowledge of a particular thing’s existence—that is, one’s self. Nevertheless, it justifies accepting as certain only the existence of the person who thinks it. If all one ever knew for certain was that one exists, and if one adhered to Descartes’s method of doubting all that is uncertain, then one would be reduced to solipsism, the view that nothing exists but one’s self and thoughts. To escape solipsism, Descartes argues that all ideas that are as “clear and distinct” as the cogito must be true, for, if they were not, the cogito also, as a member of the class of clear and distinct ideas, could be doubted. Since “I think, I am” cannot be doubted, all clear and distinct ideas must be true. On the basis of clear and distinct innate ideas, Descartes then establishes that each mind is a mental substance and each body a part of one material substance. The mind or soul is immortal, because it is unextended and cannot be broken into parts, as can extended bodies. Descartes also advances a proof for the existence of God. He begins with the proposition that he has an innate idea of God as a perfect being and then concludes that God necessarily exists, because, if he did not, he would not be perfect. This ontological argument for God’s existence, originally due to the English logician St. Anselm of Canterbury (1033/34–1109), is at the heart of Descartes’s rationalism, for it establishes certain knowledge about an existing thing solely on the basis of reasoning from innate ideas, with no help from sensory experience. Descartes then argues that, because God is perfect, he does not deceive human beings; and therefore, because God leads us to believe that the material world exists, it does exist. In this way Descartes claims to establish metaphysical foundations for the existence of his own mind, of God, and of the material world. The inherent circularity of Descartes’s reasoning was exposed by Arnauld, whose objection has come to be known as the Cartesian Circle. According to Descartes, God’s existence is established by the fact that Descartes has a clear and distinct idea of God; but the truth of Descartes’s clear and distinct ideas are guaranteed by the fact that God exists and is not a deceiver. Thus, in order to show that God exists, Descartes must assume that God exists. Physics, physiology, and morals Descartes’s general goal was to help human beings master and possess nature. He provided understanding of the trunk of the tree of knowledge in The World, Dioptrics, Meteorology, and Geometry, and he established its metaphysical roots in the Meditations. He then spent the rest of his life working on the branches of mechanics, medicine, and morals. Mechanics is the basis of his physiology and medicine, which in turn is the basis of his moral psychology. Descartes believed that all material bodies, including the human body, are machines that operate by mechanical principles. In his physiological studies, he dissected animal bodies to show how their parts move. He argued that, because animals have no souls, they do not think or feel; thus, vivisection, which Descartes practiced, is permitted. He also described the circulation of the blood but came to the erroneous conclusion that heat in the heart expands the blood, causing its expulsion into the veins. Descartes’s L’Homme, et un traité de la formation du foetus (Man, and a Treatise on the Formation of the Foetus) was published in 1664. In 1644 Descartes published Principles of Philosophy, a compilation of his physics and metaphysics. He dedicated this work to Princess Elizabeth (1618–79), daughter of Elizabeth Stuart, titular queen of Bohemia, in correspondence with whom he developed his moral philosophy. According to Descartes, a human being is a union of mind and body, two radically dissimilar substances that interact in the pineal gland. He reasoned that the pineal gland must be the uniting point because it is the only nondouble organ in the brain, and double reports, as from two eyes, must have one place to merge. He argued that each action on a person’s sense organs causes subtle matter to move through tubular nerves to the pineal gland, causing it to vibrate distinctively. These vibrations give rise to emotions and passions and also cause the body to act. Bodily action is thus the final outcome of a reflex arc that begins with external stimuli—as, for example, when a soldier sees the enemy, feels fear, and flees. The mind cannot change bodily reactions directly—for example, it cannot will the body to fight—but by altering mental attitudes, it can change the pineal vibrations from those that cause fear and fleeing to those that cause courage and fighting. Descartes argued further that human beings can be conditioned by experience to have specific emotional responses. Descartes himself, for example, had been conditioned to be attracted to cross-eyed women because he had loved a cross-eyed playmate as a child. When he remembered this fact, however, he was able to rid himself of his passion. This insight is the basis of Descartes’s defense of free will and of the mind’s ability to control the body. Despite such arguments, in his Passions of the Soul (1649), which he dedicated to Queen Christina of Sweden (reigned 1644–54), Descartes holds that most bodily actions are determined by external material causes. Descartes’s morality is anti-Jansenist and anti-Calvinist in that he maintains that the grace that is necessary for salvation can be earned and that human beings are virtuous and able to achieve salvation when they do their best to find and act upon the truth. His optimism about the ability of human reason and will to find truth and reach salvation contrasts starkly with the pessimism of the Jansenist apologist and mathematician Blaise Pascal (1623–62), who believed that salvation comes only as a gift of God’s grace. Descartes was correctly accused of holding the view of Jacobus Arminius (1560–1609), an anti-Calvinist Dutch theologian, that salvation depends on free will and good works rather than on grace. Descartes also held that, unless people believe in God and immortality, they will see no reason to be moral. Free will, according to Descartes, is the sign of God in human nature, and human beings can be praised or blamed according to their use of it. People are good, he believed, only to the extent that they act freely for the good of others; such generosity is the highest virtue. Descartes was Epicurean in his assertion that human passions are good in themselves. He was an extreme moral optimist in his belief that understanding of the good is automatically followed by a desire to do the good. Moreover, because passions are “willings” according to Descartes, to want something is the same as to will it. Descartes was also stoic, however, in his admonition that, rather than change the world, human beings should control their passions. Although Descartes wrote no political philosophy, he approved of the admonition of Seneca (c. 4 bc–ad 65) to acquiesce in the common order of things. He rejected the recommendation of Niccolò Machiavelli (1469–1527) to lie to one’s friends, because friendship is sacred and life’s greatest joy. Human beings cannot exist alone but must be parts of social groups, such as nations and families, and it is better to do good for the group than for oneself. Descartes had been a puny child with a weak chest and was not expected to live. He therefore watched his health carefully, becoming a virtual vegetarian. In 1639 he bragged that he had not been sick for 19 years and that he expected to live to 100. He told Princess Elizabeth to think of life as a comedy; bad thoughts cause bad dreams and bodily disorders. Because there is always more good than evil in life, he said, one can always be content, no matter how bad things seem. Elizabeth, inextricably involved in messy court and family affairs, was not consoled. In his later years Descartes said that he had once hoped to learn to prolong life to a century or more, but he then saw that, to achieve that goal, the work of many generations would be required; he himself had not even learned to prevent a fever. Thus, he said, instead of continuing to hope for long life, he had found an easier way, namely to love life and not to fear death. It is easy, he claimed, for a true philosopher to die tranquilly. Final years and heritage In 1644, 1647, and 1648, after 16 years in the Netherlands, Descartes returned to France for brief visits on financial business and to oversee the translation into French of the Principles, the Meditations, and the Objections and Replies. (The translators were, respectively, Picot, Charles d’Albert, duke de Luynes, and Claude Clerselier.) In 1647 he also met with Gassendi and Hobbes, and he suggested to Pascal the famous experiment of taking a barometer up Mount Puy-de-Dôme to determine the influence of the weight of the air. Picot returned with Descartes to the Netherlands for the winter of 1647–48. During Descartes’s final stay in Paris in 1648, the French nobility revolted against the crown in a series of wars known as the Fronde. Descartes left precipitously on August 17, 1648, only days before the death of his old friend Mersenne. Clerselier’s brother-in-law, Hector Pierre Chanut, who was French resident in Sweden and later ambassador, helped to procure a pension for Descartes from Louis XIV, though it was never paid. Later, Chanut engineered an invitation for Descartes to the court of Queen Christina, who by the close of the Thirty Years’ War (1618–48) had become one of the most important and powerful monarchs in Europe. Descartes went reluctantly, arriving early in October 1649. He may have gone because he needed patronage; the Fronde seemed to have destroyed his chances in Paris, and the Calvinist theologians were harassing him in the Netherlands. In Sweden—where, Descartes said, in winter men’s thoughts freeze like the water—the 22-year-old Christina perversely made the 53-year-old Descartes rise before 5:00 am to give her philosophy lessons, even though she knew of his habit of lying in bed until 11 o’clock in the morning. She also is said to have ordered him to write the verses of a ballet, The Birth of Peace (1649), to celebrate her role in the Peace of Westphalia, which ended the Thirty Years’ War. The verses in fact were not written by Descartes, though he did write the statutes for a Swedish Academy of Arts and Sciences. While delivering these statutes to the queen at 5:00 am on February 1, 1650, he caught a chill, and he soon developed pneumonia. He died in Stockholm on February 11. Many pious last words have been attributed to him, but the most trustworthy report is that of his German valet, who said that Descartes was in a coma and died without saying anything at all. Descartes’s papers came into the possession of Claude Clerselier, a pious Catholic, who began the process of turning Descartes into a saint by cutting, adding to, and selectively publishing his letters. This cosmetic work culminated in 1691 in the massive biography by Father Adrien Baillet, who was at work on a 17-volume Lives of the Saints. Even during Descartes’s lifetime there were questions about whether he was a Catholic apologist, primarily concerned with supporting Christian doctrine, or an atheist, concerned only with protecting himself with pious sentiments while establishing a deterministic, mechanistic, and materialistic physics. These questions remain difficult to answer, not least because all the papers, letters, and manuscripts available to Clerselier and Baillet are now lost. In 1667 the Roman Catholic church made its own decision by putting Descartes’s works on the Index Librorum Prohibitorum (Latin: “Index of Prohibited Books”) on the very day his bones were ceremoniously placed in Sainte-Geneviève-du-Mont in Paris. During his lifetime, Protestant ministers in the Netherlands called Descartes a Jesuit and a papist—which is to say an atheist. He retorted that they were intolerant, ignorant bigots. Up to about 1930, a majority of scholars, many of whom were religious, believed that Descartes’s major concerns were metaphysical and religious. By the late 20th century, however, numerous commentators had come to believe that Descartes was a Catholic in the same way he was a Frenchman and a royalist—that is, by birth and by convention. Descartes himself said that good sense is destroyed when one thinks too much of God. He once told a German protégée, Anna Maria van Schurman (1607–78), who was known as a painter and a poet, that she was wasting her intellect studying Hebrew and theology. He also was perfectly aware of—though he tried to conceal—the atheistic potential of his materialist physics and physiology. Descartes seemed indifferent to the emotional depths of religion. Whereas Pascal trembled when he looked into the infinite universe and perceived the puniness and misery of man, Descartes exulted in the power of human reason to understand the cosmos and to promote happiness, and he rejected the view that human beings are essentially miserable and sinful. He held that it is impertinent to pray to God to change things. Instead, when we cannot change the world, we must change ourselves. Richard A. Watson

 

Modern philosophy » The rise of empiricism and rationalism » The rationalism of Spinoza and Leibniz

The tradition of Continental rationalism was carried on by two philosophers of genius: the Dutch Jewish philosopher Benedict de Spinoza (1632–77) and his younger contemporary Gottfried Wilhelm Leibniz (1646–1716), a Leipzig scholar and polymath. Whereas Bacon’s philosophy had been a search for method in science and Descartes’s basic aim had been the achievement of scientific certainty, Spinoza’s speculative system was one of the most comprehensive of the early modern period. In certain respects Spinoza had much in common with Hobbes: a mechanistic worldview and even a political philosophy that sought political stability in centralized power. Yet Spinoza introduced a conception of philosophizing that was new to the Renaissance; philosophy became a personal and moral quest for wisdom and the achievement of human perfection.

Spinoza’s magnum opus, the Ethics, borrowed much from Descartes: the goal of a rational understanding of principles, the terminology of “substance” and “clear and distinct ideas,” and the expression of philosophical knowledge in a complete deductive system using the geometric model of the Elements of Euclid (flourished c. 300 bc). Spinoza conceived of the universe pantheistically as a single infinite substance, which he called “God,” with the dual attributes (or aspects) of thought and extension. Extension is differentiated into plural “modes,” or particular things, and the world as a whole possesses the properties of a timeless logical system—a complex of completely determined causes and effects. For Spinoza, the wisdom that philosophy seeks is ultimately achieved when one perceives the universe in its wholeness through the “intellectual love of God,” which merges the finite individual with eternal unity and provides the mind with the pure joy that is the final achievement of its search.

Whereas the basic elements of the Spinozistic worldview are given in the Ethics, Leibniz’s philosophy must be pieced together from numerous brief expositions, which seem to be mere philosophical interludes in an otherwise busy life. But the philosophical form is deceptive. Leibniz was a mathematician (he and Sir Isaac Newton independently invented the infinitesimal calculus), a jurist (he codified the laws of Mainz), a diplomat, a historian to royalty, and a court librarian in a princely house. Yet he was also one of the most original philosophers of the early modern period. His chief contributions were in the fields of logic, in which he was a truly brilliant innovator, and metaphysics, in which he provided a rationalist alternative to the philosophies of Descartes and Spinoza. Leibniz conceived of logic as a mathematical calculus. He was the first to distinguish “truths of reason” from “truths of fact” and to contrast the necessary propositions of logic and mathematics, which hold in all “possible worlds,” with the contingent propositions of science, which hold only in some possible worlds (including the actual world). He saw clearly that, as the first kind of proposition is governed by the principle of contradiction (a proposition and its negation cannot both be true), the second is governed by the principle of sufficient reason (nothing exists or is the case without a sufficient reason).

In metaphysics, Leibniz’s pluralism contrasted with Descartes’s dualism and Spinoza’s monism. Leibniz posited the existence of an infinite number of spiritual substances, which he called “monads,” each different, each a percipient of the universe around it, and each mirroring that universe from its own point of view. However, the differences between Leibniz’s philosophy and that of Descartes and Spinoza are less significant than their similarities, in particular their extreme rationalism. In the Principes de la nature et de la grâce fondés en raison (1714; “Principles of Nature and of Grace Founded in Reason”), Leibniz stated a maxim that could fairly represent the entire school:

True reasoning depends upon necessary or eternal truths, such as those of logic, numbers, geometry, which establish an indubitable connection of ideas and unfailing consequences.

	Benedict de Spinoza Dutch-Jewish philosopher Hebrew forename Baruch, Latin forename Bendictus, Portuguese Bento De Espinosa born Nov. 24, 1632, Amsterdam died Feb. 21, 1677, The Hague Main Dutch-Jewish philosopher, the foremost exponent of 17th-century Rationalism. Early life and career. Spinoza’s grandfather and father were Portuguese and had been crypto-Jews after the Spanish Inquisition had compelled them to embrace Christianity. Later, after Holland’s successful revolt against Spain and the granting of religious freedom, they found refuge in Amsterdam. His mother, who also came from Portugal, died when Benedict was barely six years old. The Spinozas were prosperous merchants and respected members of the Jewish community, and it may be assumed that Spinoza attended the school for Jewish boys founded in Amsterdam in about 1638. Outside school hours the boys had private lessons in secular subjects. Spinoza was taught Latin by a German scholar, who may also have taught him German; and he knew to some extent all of the other significant continental languages. In March 1654 Benedict’s father died. There was some litigation over the estate, with Benedict’s only surviving stepsister claiming it all. Benedict won the lawsuit but allowed her to retain nearly everything. His studies so far had been mainly Jewish, but he was an independent thinker and had found more than enough in his Jewish studies to wean him from orthodox doctrines and interpretations of Scripture; moreover, the tendency to revolt against tradition and authority was much in the air in the 17th century. But the Jewish religious leaders in Amsterdam were fearful that heresies (which were no less anti-Christian than anti-Jewish) might give offense in a country that did not yet regard the Jews as citizens. Spinoza soon incurred the disapproval of the synagogue authorities. In conversations with other students, he had held that there is nothing in the Bible to support the views that God had no body, that angels really exist, or that the soul is immortal; and he had also expressed his belief that the author of the Pentateuch (the first five books of the Bible) was no wiser in physics or even in theology than were they, the students. The Jewish authorities, after trying vainly to silence Spinoza with bribes and threats, excommunicated him in July 1656, and he was banished from Amsterdam for a short period by the civil authorities. There is no evidence that he had really wanted to break away from the Jewish community, and indeed the scanty knowledge available would suggest the opposite. On Dec. 5, 1655, for example, he had attended the synagogue and made an offering that, in view of his poverty, must have been a rare event for him, and, about the time of his excommunication, he had addressed a defense of his views to the synagogue. Among Spinoza’s Christian acquaintances was Franciscus van den Enden, who was a former Jesuit, an ardent classical scholar, and something of a poet and dramatist and who had opened a school in Amsterdam. For a time, Spinoza stayed with him, helping with the teaching of the schoolchildren and receiving aid in his own further education. In this way he improved his knowledge of Latin, learned some Greek, and was introduced to Neoscholastic philosophy. It may have also been through van den Enden’s school that Spinoza became acquainted with the “new philosophy” of René Descartes, later acknowledged to be the father of modern philosophy. Spinoza’s other Christian acquaintances were mostly of the Collegiants, a brotherhood that later merged with the Mennonites; they were especially interested in Cartesianism, the dualistic philosophy of Descartes and his followers. At the same time, he was becoming expert at making lenses, supporting himself partly by grinding and polishing lenses for spectacles, telescopes, and microscopes; he also did tutoring. A kind of reading and discussion circle for the study of religious and philosophical problems came into being under the guidance of Spinoza. In order to collect his thoughts, however, and reduce them to a system, he withdrew in 1660 to Rijnsburg, a quiet village on the Rhine, near Leiden. Rijnsburg was the headquarters of the Collegiants, and Spinoza’s lodgings there were with a surgeon named Hermann Homan. In Homan’s cottage Spinoza wrote Korte Verhandeling van God, de Mensch en deszelfs Welstand (written c. 1662; Spinoza’s Short Treatise on God, Man, and His Well-Being, 1910) and Tractatus de Intellectus Emendatione (“Treatise on the Correction of the Understanding”), both of which were ready by April 1662. He also completed the greater part of his geometrical version of Descartes’s Principia Philosophiae and the first book of his Ethica. Spinoza’s attitude in these works already showed a departure from Cartesianism. It was also during this stay that he met Heinrich Oldenburg, soon to become one of the two first secretaries of the Royal Society in London. Influence of Descartes and the geometrical method. His version of Descartes’s Principia was prepared while Spinoza was giving instruction in the philosophy of Descartes to a private pupil. It was published by his Cartesian friends under the title Renati des Cartes Principiorum Philosophiae Pars I et II, More Geometrico Demonstratae, per Benedictum de Spinoza (1663), with an introduction explaining that Spinoza did not share the views expressed in the book. This was the only book published in Spinoza’s lifetime with his name on the title page. The philosophy of Spinoza may thus be regarded as a development from and a reaction to that of his contemporary Descartes (1596–1650). Though it has been argued that Spinoza was also much influenced by medieval philosophy (especially Jewish), he seems to have been much more conscious of the Cartesian influence, and his most striking doctrines are most easily understood as solutions of Cartesian difficulties. Clearly, he had studied Descartes in detail. He accepted Descartes’s physics in general, though he did express some dissatisfaction with it toward the end of his life. As for the Cartesian metaphysics, he found three unsatisfactory features: the transcendence of God, the substantial dualism of mind and body, and the ascription of free will both to God and to human beings. In Spinoza’s eyes, those doctrines made the world unintelligible. It was impossible to explain the relation between God and the world or between mind and body or to account for events occasioned by free will. The publication of Spinoza’s version of Descartes’s Principia had been intended to prepare the way for that of his own philosophy, for he had both to secure the patronage of influential men and to show the more philosophically minded that his rejection of Cartesianism was not out of ignorance. Spinoza became dissatisfied with the informal method of exposition that he had adopted in the Korte Verhandeling and the De Intellectus Emendatione and turned instead to the geometrical method in the manner of Euclid’s Elements. He assumed without question that it is possible to construct a system of metaphysics that will render it completely intelligible. It is therefore possible, in his view, to present metaphysics deductively—that is, as a series of theorems derived by necessary steps from self-evident premises expressed in terms that are either self-explanatory or defined with unquestionable correctness. His masterpiece, the Ethica, was set out in this manner—Ordine Geometrico Demonstrata, according to the reading of its subtitle. Its first part, “De Deo” (“Concerning God”), was finished and in the hands of his friends early in 1663. Initially the work was intended to have three parts only, but it eventually appeared (in 1677) in five parts. Spinoza’s desire for an impersonal presentation was probably his chief motive for adopting the geometrical method, appreciating that the method guarantees true conclusions only if the axioms are true and the definitions correct. Spinoza, like his contemporaries, held that definitions are not arbitrary but that there is a sense in which they may be correct or incorrect. The question was discussed at length in his unfinished Tractatus de Intellectus Emendatione. A sound definition, he held, should make clear the possibility or the necessity of the existence of the object defined. Because the Ethica begins with the definition of “substance,” the necessary existent, the entire system is vulnerable to anyone disputing that definition, however cogent the subsequent reasoning may be. In fact, as Gottfried Wilhelm Leibniz, a Rationalist philosopher and mathematician, pointed out, though the system is closely knit, its demonstrations do not proceed with mathematical rigour. Period of the “Ethica.” In June 1663 Spinoza moved to Voorburg, near The Hague, and it appears that by June 1665 he was nearing the completion of the three-part version of the Ethica. During the next few years, however, he was at work on his Tractatus Theologico-Politicus, which was published anonymously at Amsterdam in 1670. This work aroused great interest and was to go through five editions in as many years. It was intended “to show that not only is liberty to philosophize compatible with devout piety and with the peace of the state, but that to take away such liberty is to destroy the public peace and even piety itself.” As this work shows, Spinoza was far ahead of his time in advocating the application of the historical method to the interpretation of the biblical sources. He argued that the inspiration of the prophets of the Old Testament extended only to their moral and practical doctrines and that their factual beliefs were merely those appropriate to their time and are not philosophically significant. Complete freedom of scientific and metaphysical speculation is therefore consistent with all that is important in the Bible. Miracles are explained as natural events misinterpreted and stressed for their moral effect. In May 1670 Spinoza moved to The Hague, where he remained until his death. He began to compose a Hebrew grammar, Compendium Grammatices Linguae Hebraeae, but did not finish it; instead, he returned to the Ethica, although the prospect of its publication became increasingly remote. There were many denunciations of his Tractatus Theologico-Politicus as an instrument “forged in hell by a renegade Jew and the devil.” When the Ethica was completed in 1675, Spinoza had to abandon the idea of publishing it, though manuscript copies were circulated among his close friends. Last years and posthumous influence. Spinoza concentrated his attention on political problems and began his Tractatus Politicus, which he did not live to finish. During the post-Ethica period, he was visited by several important people, among them Ehrenfried Walter von Tschirnhaus (in 1675), a scientist and philosopher, and Gottfried Wilhelm Leibniz (in 1676), like Spinoza, one of the foremost Rationalists of the time. Leibniz, having heard of Spinoza as an authority on optics, had sent him an optical tract and had then received from Spinoza a copy of the Tractatus Theologico-Politicus, which deeply interested him. According to Leibniz’ own account, he “conversed with him often and at great length.” Spinoza, however, was now in an advanced stage of consumption, aggravated by the inhaling of glass dust from the polishing of lenses in his shop. He died in 1677, leaving no heir, and his few possessions were sold by auction. These included about 160 books, the catalog of which has been preserved. In accordance with Spinoza’s previous instructions, several of his friends prepared his manuscripts secretly for the press, and they were sent to a publisher in Amsterdam. The Opera Posthuma (Dutch version: Nagelate Schriften), published before the end of 1677, was composed of the Ethica, Tractatus Politicus, and Tractatus de Intellectus Emendatione, as well as letters and the Hebrew grammar. His Stelkonstige reeckening van den regenboog (“On the Rainbow”) and his Reeckening van kanssen (“On the Calculation of Chances”) were printed together in 1687. The Korte Verhandeling was lost to the world until E. Boehmer’s publication of it in 1852. Spinoza has an assured place in the intellectual history of the Western world, though his direct influence on technical philosophy has not been great. Throughout the 18th century he was almost universally decried as an atheist—or sometimes used as a cover for the detailing of atheist ideas. The tone had been set by Pierre Bayle, a Skeptical philosopher and encyclopaedist, in whose Dictionnaire historique et critique Spinozism was described as “the most monstrous hypothesis imaginable, the most absurd”; and even David Hume, a Scottish Skeptic and historian, felt obliged to speak of the “hideous hypothesis” of Spinoza. Spinoza was rendered intellectually respectable by the efforts of literary critics, especially of the Germans G.E. Lessing and J.W. von Goethe and the English poet S.T. Coleridge, who admired the man and found austere excitement in his works, in which they saw an intensely religious attitude entirely divorced from dogma. Spinoza has also been much studied by professional philosophers since the beginning of the 19th century. Both absolute Idealists and Marxists have read their own doctrines into his work, and Empiricists, while rejecting his metaphysical approach, have developed certain detailed suggestions from his theory of knowledge and psychology.
	Gottfried Wilhelm Leibniz German philosopher and mathematician born July 1 [June 21, old style], 1646, Leipzig died November 14, 1716, Hannover, Hanover Main German philosopher, mathematician, and political adviser, important both as a metaphysician and as a logician and distinguished also for his independent invention of the differential and integral calculus. Early life and education Leibniz was born into a pious Lutheran family near the end of the Thirty Years’ War, which had laid Germany in ruins. As a child, he was educated in the Nicolai School but was largely self-taught in the library of his father, who had died in 1652. At Easter time in 1661, he entered the University of Leipzig as a law student; there he came into contact with the thought of men who had revolutionized science and philosophy—men such as Galileo, Francis Bacon, Thomas Hobbes, and René Descartes. Leibniz dreamed of reconciling—a verb that he did not hesitate to use time and again throughout his career—these modern thinkers with the Aristotle of the Scholastics. His baccalaureate thesis, De Principio Individui (“On the Principle of the Individual”), which appeared in May 1663, was inspired partly by Lutheran nominalism (the theory that universals have no reality but are mere names) and emphasized the existential value of the individual, who is not to be explained either by matter alone or by form alone but rather by his whole being (entitate tota). This notion was the first germ of the future “monad.” In 1666 he wrote De Arte Combinatoria (“On the Art of Combination”), in which he formulated a model that is the theoretical ancestor of some modern computers: all reasoning, all discovery, verbal or not, is reducible to an ordered combination of elements, such as numbers, words, sounds, or colours. After completing his legal studies in 1666, Leibniz applied for the degree of doctor of law. He was refused because of his age and consequently left his native city forever. At Altdorf—the university town of the free city of Nürnberg—his dissertation De Casibus Perplexis (“On Perplexing Cases”) procured him the doctor’s degree at once, as well as the immediate offer of a professor’s chair, which, however, he declined. During his stay in Nürnberg, he met Johann Christian, Freiherr von Boyneburg, one of the most distinguished German statesmen of the day. Boyneburg took him into his service and introduced him to the court of the prince elector, the archbishop of Mainz, Johann Philipp von Schönborn, where he was concerned with questions of law and politics. King Louis XIV of France was a growing threat to the German Holy Roman Empire. To ward off this danger and divert the King’s interests elsewhere, the Archbishop hoped to propose to Louis a project for an expedition into Egypt; because he was using religion as a pretext, he expressed the hope that the project would promote the reunion of the church. Leibniz, with a view toward this reunion, worked on the Demonstrationes Catholicae. His research led him to situate the soul in a point—this was new progress toward the monad—and to develop the principle of sufficient reason (nothing occurs without a reason). His meditations on the difficult theory of the point were related to problems encountered in optics, space, and movement; they were published in 1671 under the general title Hypothesis Physica Nova (“New Physical Hypothesis”). He asserted that movement depends, as in the theory of the German astronomer Johannes Kepler, on the action of a spirit (God). In 1672 the Elector sent the young jurist on a mission to Paris, where he arrived at the end of March. In September, Leibniz met with Antoine Arnauld, a Jansenist theologian (Jansenism was a nonorthodox Roman Catholic movement that spawned a rigoristic form of morality) known for his writings against the Jesuits. Leibniz sought Arnauld’s help for the reunion of the church. He was soon left without protectors by the deaths of Freiherr von Boyneburg in December 1672 and of the Elector of Mainz in February 1673; he was now, however, free to pursue his scientific studies. In search of financial support, he constructed a calculating machine and presented it to the Royal Society during his first journey to London, in 1673. Late in 1675 Leibniz laid the foundations of both integral and differential calculus. With this discovery, he ceased to consider time and space as substances—another step closer to monadology. He began to develop the notion that the concepts of extension and motion contained an element of the imaginary, so that the basic laws of motion could not be discovered merely from a study of their nature. Nevertheless, he continued to hold that extension and motion could provide a means for explaining and predicting the course of phenomena. Thus, contrary to Descartes, Leibniz held that it would not be contradictory to posit that this world is a well-related dream. If visible movement depends on the imaginary element found in the concept of extension, it can no longer be defined by simple local movement; it must be the result of a force. In criticizing the Cartesian formulation of the laws of motion, known as mechanics, Leibniz became, in 1676, the founder of a new formulation, known as dynamics, which substituted kinetic energy for the conservation of movement. At the same time, beginning with the principle that light follows the path of least resistance, he believed that he could demonstrate the ordering of nature toward a final goal or cause. The Hanoverian period Leibniz continued his work but was still without an income-producing position. By October 1676, however, he had accepted a position in the employment of John Frederick, the duke of Braunschweig-Lüneburg. John Frederick, a convert to Catholicism from Lutheranism in 1651, had become duke of Hanover in 1665. He appointed Leibniz librarian, but, beginning in February 1677, Leibniz solicited the post of councillor, which he was finally granted in 1678. It should be noted that, among the great philosophers of his time, he was the only one who had to earn a living. As a result, he was always a jack-of-all-trades to royalty. Trying to make himself useful in all ways, Leibniz proposed that education be made more practical, that academies be founded; he worked on hydraulic presses, windmills, lamps, submarines, clocks, and a wide variety of mechanical devices; he devised a means of perfecting carriages and experimented with phosphorus. He also developed a water pump run by windmills, which ameliorated the exploitation of the mines of the Harz Mountains, and he worked in these mines as an engineer frequently from 1680 to 1685. Leibniz is considered to be among the creators of geology because of the observations he compiled there, including the hypothesis that the Earth was at first molten. These many occupations did not stop his work in mathematics: In March 1679 he perfected the binary system of numeration (i.e., using two as a base), and at the end of the same year he proposed the basis for analysis situs, now known as general topology, a branch of mathematics that deals with selected properties of collections of related physical or abstract elements. He was also working on his dynamics and his philosophy, which was becoming increasingly anti-Cartesian. At this point, Duke John Frederick died on Jan. 7, 1680, and his brother, Ernest Augustus I, succeeded him. France was growing more intolerant at home—from 1680 to 1682 there were harsh persecutions of the Protestants that paved the way for the revocation of the Edict of Nantes on Oct. 18, 1685—and increasingly menacing on its frontiers, for as early as 1681, despite the reigning peace, Louis XIV took Strasbourg and laid claim to 10 cities in Alsace. France was thus becoming a real danger to the empire, which had already been shaken on the east by a Hungarian revolt and by the advance of the Turks, who had been stopped only by the victory of John III Sobieski, king of Poland, at the siege of Vienna in 1683. Leibniz served both his prince and the empire as a patriot. He suggested to his prince a means of increasing the production of linen and proposed a process for the desalinization of water; he recommended classifying the archives and wrote, in both French and Latin, a violent pamphlet against Louis XIV. During this same period Leibniz continued to perfect his metaphysical system through research into the notion of a universal cause of all being, attempting to arrive at a starting point that would reduce reasoning to an algebra of thought. He also continued his developments in mathematics; in 1681 he was concerned with the proportion between a circle and a circumscribed square and, in 1684, with the resistance of solids. In the latter year he published Nova Methodus pro Maximis et Minimis (“New Method for the Greatest and the Least”), which was an exposition of his differential calculus. Leibniz’ noted Meditationes de Cognitione, Veritate et Ideis (Reflections on Knowledge, Truth, and Ideas) appeared at this time and defined his theory of knowledge: things are not seen in God—as Nicolas Malebranche suggested—but rather there is an analogy, a strict relation, between God’s ideas and man’s, an identity between God’s logic and man’s. In February 1686, Leibniz wrote his Discours de métaphysique (Discourse on Metaphysics). In the March publication of Acta, he disclosed his dynamics in a piece entitled Brevis Demonstratio Erroris Memorabilis Cartesii et Aliorum Circa Legem Naturae (“Brief Demonstration of the Memorable Error of Descartes and Others About the Law of Nature”). A further development of Leibniz’ views, revealed in a text written in 1686 but long unpublished, was his generalization concerning propositions that in every true affirmative proposition, whether necessary or contingent, the predicate is contained in the notion of the subject. It can be said that, at this time, with the exception of the word monad (which did not appear until 1695), his philosophy of monadology was defined. In 1685 Leibniz was named historian for the House of Brunswick and, on this occasion, Hofrat (“court adviser”). His job was to prove, by means of genealogy, that the princely house had its origins in the House of Este, an Italian princely family, which would allow Hanover to lay claim to a ninth electorate. In search of these documents, Leibniz began travelling in November 1687. Going by way of southern Germany, he arrived in Austria, where he learned that Louis XIV had once again declared a state of war; in Vienna, he was well received by the Emperor; he then went to Italy. Everywhere he went, he met scientists and continued his scholarly work, publishing essays on the movement of celestial bodies and on the duration of things. He returned to Hanover in mid-July 1690. His efforts had not been in vain. In October 1692 Ernest Augustus obtained the electoral investiture. Until the end of his life, Leibniz continued his duties as historian. He did not, however, restrict himself to a genealogy of the House of Brunswick; he enlarged his goal to a history of the Earth, which included such matters as geological events and descriptions of fossils. He searched by way of monuments and linguistics for the origins and migrations of peoples; then for the birth and progress of the sciences, ethics, and politics; and, finally, for the elements of a historia sacra. In this project of a universal history, Leibniz never lost sight of the fact that everything interlocks. Even though he did not succeed in writing this history, his effort was influential because he devised new combinations of old ideas and invented totally new ones. In 1691 Leibniz was named librarian at Wolfenbüttel and propagated his discoveries by means of articles in scientific journals. In 1695 he explained a portion of his dynamic theory of motion in the Système nouveau (“New System”), which treated the relationship of substances and the preestablished harmony between the soul and the body: God does not need to bring about man’s action by means of his thoughts, as Malebranche asserted, or to wind some sort of watch in order to reconcile the two; rather, the Supreme Watchmaker has so exactly matched body and soul that they correspond—they give meaning to each other—from the beginning. In 1697, De Rerum Originatione (On the Ultimate Origin of Things) tried to prove that the ultimate origin of things can be none other than God. In 1698, De Ipsa Natura (“On Nature Itself”) explained the internal activity of nature in terms of Leibniz’ theory of dynamics. All of these writings opposed Cartesianism, which was judged to be damaging to faith. Plans for the creation of German academies followed in rapid succession. With the help of the electress Sophia Charlotte, daughter of Ernest Augustus and soon to become the first queen of Prussia (January 1701), the German Academy of Sciences in Berlin was founded on July 11, 1700. On Jan. 23, 1698, Ernest Augustus died, and his son, George Louis, succeeded him. Leibniz found himself confronted with an uneducated, boorish prince, a reveller who kept him in the background. Leibniz took advantage of every pretext to leave Hanover; he was constantly on the move; his only comfort lay in his friendship with Sophia Charlotte and her mother, Princess Sophia. Once again, he set to work on the reunion of the church: in Berlin, it was a question of uniting the Lutherans and the Calvinists; in Paris, he had to subdue Bishop Bénigne Bossuet’s opposition; in Vienna (to which Leibniz returned in 1700) he enlisted the support of the Emperor, which carried great weight; in England, it was the Anglicans who needed convincing. The death in England of William, duke of Gloucester, in 1700 made George Louis, great-grandson of James I, a possible heir to the throne. It fell to Leibniz, jurist and historian, to develop his arguments concerning the rights of the House of Braunschweig-Lüneburg with respect to this succession. The War of the Spanish Succession began in March 1701 and did not come to a close until September 1714, with the Treaty of Baden. Leibniz followed its episodes as a patriot hostile to Louis XIV. His fame as a philosopher and scientist had by this time spread all over Europe; he was named a foreign member by the Academy of Sciences of Paris in 1700 and was in correspondence with most of the important European scholars of the day. If he was publishing little at this point, it was because he was writing Théodicée, which was published in 1710. In this work he set down his ideas on divine justice. Leibniz was impressed with the qualities of the Russian tsar Peter the Great, and in October 1711 the ruler received him for the first time. Following this, he stayed in Vienna until September 1714, and during this time the Emperor promoted him to the post of Reichhofrat (“adviser to the empire”) and gave him the title of Freiherr (“baron”). About this time he wrote the Principes de la nature et de la Grâce fondés en raison, which inaugurated a kind of preestablished harmony between these two orders. Further, in 1714 he wrote the Monadologia, which synthesized the philosophy of the Théodicée. In August 1714, the death of Queen Anne brought George Louis to the English throne under the name of George I. Returning to Hanover, where he was virtually placed under house arrest, Leibniz set to work once again on the Annales Imperii Occidentis Brunsvicenses (1843–46; “Braunschweig Annals of the Western Empire”). At Bad-Pyrmont, he met with Peter the Great for the last time in June 1716. From that point on, he suffered greatly from gout and was confined to his bed until his death. Leibniz was a man of medium height with a stoop, broad-shouldered but bandy-legged, as capable of thinking for several days sitting in the same chair as of travelling the roads of Europe summer and winter. He was an indefatigable worker, a universal letter writer (he had more than 600 correspondents), a patriot and cosmopolitan, a great scientist, and one of the most powerful spirits of Western civilization. Yvon Belaval