Aristotle
Greek philosopher
Greek Aristoteles
born 384 bc, Stagira, Chalcidice, Greece
died 322, Chalcis, Euboea
Overview
Greek philosopher and scientist whose thought determined the course of
Western intellectual history for two millenia.
He was the son of the court physician to Amyntas III, grandfather of
Alexander the Great. In 367 he became a student at the Academy of Plato
in Athens; he remained there for 20 years. After Plato’s death in
348/347, he returned to Macedonia, where he became tutor to the young
Alexander. In 335 he founded his own school in Athens, the Lyceum. His
intellectual range was vast, covering most of the sciences and many of
the arts. He worked in physics, chemistry, biology, zoology, and botany;
in psychology, political theory, and ethics; in logic and metaphysics;
and in history, literary theory, and rhetoric. He invented the study of
formal logic, devising for it a finished system, known as syllogistic,
that was considered the sum of the discipline until the 19th century;
his work in zoology, both observational and theoretical, also was not
surpassed until the 19th century. His ethical and political theory,
especially his conception of the ethical virtues and of human
flourishing (“happiness”), continue to exert great influence in
philosophical debate. He wrote prolifically; his major surviving works
include the Organon, De Anima (“On the Soul”), Physics, Metaphysics,
Nicomachean Ethics, Eudemian Ethics, Magna Moralia, Politics, Rhetoric,
and Poetics, as well as other works on natural history and science. See
also teleology.
Main
ancient Greek philosopher and scientist, one of the greatest
intellectual figures of Western history. He was the author of a
philosophical and scientific system that became the framework and
vehicle for both Christian Scholasticism and medieval Islamic
philosophy. Even after the intellectual revolutions of the Renaissance,
the Reformation, and the Enlightenment, Aristotelian concepts remained
embedded in Western thinking.
Aristotle’s intellectual range was vast, covering most of the
sciences and many of the arts, including biology, botany, chemistry,
ethics, history, logic, metaphysics, rhetoric, philosophy of mind,
philosophy of science, physics, poetics, political theory, psychology,
and zoology. He was the founder of formal logic, devising for it a
finished system that for centuries was regarded as the sum of the
discipline; and he pioneered the study of zoology, both observational
and theoretical, in which some of his work remained unsurpassed until
the 19th century. But he is, of course, most outstanding as a
philosopher. His writings in ethics and political theory as well as in
metaphysics and the philosophy of science continue to be studied, and
his work remains a powerful current in contemporary philosophical
debate.
This article deals with Aristotle’s life and thought. For the later
development of Aristotelian philosophy, see Aristotelianism. For
treatment of Aristotelianism in the full context of Western philosophy,
see philosophy, Western.
Life » The Academy
Aristotle was born on the Chalcidic peninsula of Macedonia, in northern
Greece. His father, Nicomachus, was the physician of Amyntas III
(reigned c. 393–c. 370 bc), king of Macedonia and grandfather of
Alexander the Great (reigned 336–323 bc). After his father’s death in
367, Aristotle migrated to Athens, where he joined the Academy of Plato
(c. 428–c. 348 bc). He remained there for 20 years as Plato’s pupil and
colleague.
Many of Plato’s later dialogues date from these decades, and they may
reflect Aristotle’s contributions to philosophical debate at the
Academy. Some of Aristotle’s writings also belong to this period, though
mostly they survive only in fragments. Like his master, Aristotle wrote
initially in dialogue form, and his early ideas show a strong Platonic
influence. His dialogue Eudemus, for example, reflects the Platonic view
of the soul as imprisoned in the body and as capable of a happier life
only when the body has been left behind. According to Aristotle, the
dead are more blessed and happier than the living, and to die is to
return to one’s real home.
Another youthful work, the Protrepticus (“Exhortation”), has been
reconstructed by modern scholars from quotations in various works from
late antiquity. Everyone must do philosophy, Aristotle claims, because
even arguing against the practice of philosophy is itself a form of
philosophizing. The best form of philosophy is the contemplation of the
universe of nature; it is for this purpose that God made human beings
and gave them a godlike intellect. All else—strength, beauty, power, and
honour—is worthless.
It is possible that two of Aristotle’s surviving works on logic and
disputation, the Topics and the Sophistical Refutations, belong to this
early period. The former demonstrates how to construct arguments for a
position one has already decided to adopt; the latter shows how to
detect weaknesses in the arguments of others. Although neither work
amounts to a systematic treatise on formal logic, Aristotle can justly
say, at the end of the Sophistical Refutations, that he has invented the
discipline of logic—nothing at all existed when he started.
During Aristotle’s residence at the Academy, King Philip II of
Macedonia (reigned 359–336 bc) waged war on a number of Greek
city-states. The Athenians defended their independence only
half-heartedly, and, after a series of humiliating concessions, they
allowed Philip to become, by 338, master of the Greek world. It cannot
have been an easy time to be a Macedonian resident in Athens.
Within the Academy, however, relations seem to have remained cordial.
Aristotle always acknowledged a great debt to Plato; he took a large
part of his philosophical agenda from Plato, and his teaching is more
often a modification than a repudiation of Plato’s doctrines. Already,
however, Aristotle was beginning to distance himself from Plato’s theory
of Forms, or Ideas (eidos; see form). (The word Form, when used to refer
to Forms as Plato conceived them, is often capitalized in the scholarly
literature; when used to refer to forms as Aristotle conceived them, it
is conventionally lowercased.) Plato had held that, in addition to
particular things, there exists a suprasensible realm of Forms, which
are immutable and everlasting. This realm, he maintained, makes
particular things intelligible by accounting for their common natures: a
thing is a horse, for example, by virtue of the fact that it shares in,
or imitates, the Form of “Horse.” In a lost work, On Ideas, Aristotle
maintains that the arguments of Plato’s central dialogues establish only
that there are, in addition to particulars, certain common objects of
the sciences. In his surviving works as well, Aristotle often takes
issue with the theory of Forms, sometimes politely and sometimes
contemptuously. In his Metaphysics he argues that the theory fails to
solve the problems it was meant to address. It does not confer
intelligibility on particulars, because immutable and everlasting Forms
cannot explain how particulars come into existence and undergo change.
All the theory does, according to Aristotle, is introduce new entities
equal in number to the entities to be explained—as if one could solve a
problem by doubling it.(See below Doctrines: Physics and metaphysics:
Form.)
Life » Travels
When Plato died about 348, his nephew Speusippus became head of the
Academy, and Aristotle left Athens. He migrated to Assus, a city on the
northwestern coast of Anatolia (in present-day Turkey), where Hermias, a
graduate of the Academy, was ruler. Aristotle became a close friend of
Hermias and eventually married his ward Pythias. Aristotle helped
Hermias to negotiate an alliance with Macedonia, which angered the
Persian king, who had Hermias treacherously arrested and put to death.
Aristotle saluted Hermias’s memory in Ode to Virtue, his only surviving
poem.
While in Assus and during the subsequent few years when he lived in
the city of Mytilene on the island of Lesbos, Aristotle carried out
extensive scientific research, particularly in zoology and marine
biology. This work was summarized in a book later known, misleadingly,
as The History of Animals, to which Aristotle added two short treatises,
On the Parts of Animals and On the Generation of Animals. Although
Aristotle did not claim to have founded the science of zoology, his
detailed observations of a wide variety of organisms were quite without
precedent. He—or one of his research assistants—must have been gifted
with remarkably acute eyesight, since some of the features of insects
that he accurately reports were not again observed until the invention
of the microscope in the 17th century.
The scope of Aristotle’s scientific research is astonishing. Much of
it is concerned with the classification of animals into genus and
species; more than 500 species figure in his treatises, many of them
described in detail. The myriad items of information about the anatomy,
diet, habitat, modes of copulation, and reproductive systems of mammals,
reptiles, fish, and insects are a melange of minute investigation and
vestiges of superstition. In some cases his unlikely stories about rare
species of fish were proved accurate many centuries later. In other
places he states clearly and fairly a biological problem that took
millennia to solve, such as the nature of embryonic development.
Despite an admixture of the fabulous, Aristotle’s biological works
must be regarded as a stupendous achievement. His inquiries were
conducted in a genuinely scientific spirit, and he was always ready to
confess ignorance where evidence was insufficient. Whenever there is a
conflict between theory and observation, one must trust observation, he
insisted, and theories are to be trusted only if their results conform
with the observed phenomena.
About eight years after the death of Hermias, in 343 or 342,
Aristotle was summoned by Philip II to the Macedonian capital at Pella
to act as tutor to Philip’s 13-year-old son, the future Alexander the
Great. Little is known of the content of Aristotle’s instruction;
although the Rhetoric to Alexander was included in the Aristotelian
corpus for centuries, it is now commonly regarded as a forgery. By 326
Alexander had made himself master of an empire that stretched from the
Danube to the Indus and included Libya and Egypt. Ancient sources report
that during his campaigns Alexander arranged for biological specimens to
be sent to his tutor from all parts of Greece and Asia Minor.
Life » The Lyceum
While Alexander was conquering Asia, Aristotle, now 50 years old, was in
Athens. Just outside the city boundary, he established his own school in
a gymnasium known as the Lyceum. He built a substantial library and
gathered around him a group of brilliant research students, called
“peripatetics” from the name of the cloister (peripatos) in which they
walked and held their discussions. The Lyceum was not a private club
like the Academy; many of the lectures there were open to the general
public and given free of charge.
Most of Aristotle’s surviving works, with the exception of the
zoological treatises, probably belong to this second Athenian sojourn.
There is no certainty about their chronological order, and indeed it is
probable that the main treatises—on physics, metaphysics, psychology,
ethics, and politics—were constantly rewritten and updated. Every
proposition of Aristotle is fertile of ideas and full of energy, though
his prose is commonly neither lucid nor elegant.
Aristotle’s works, though not as polished as Plato’s, are systematic
in a way that Plato’s never were. Plato’s dialogues shift constantly
from one topic to another, always (from a modern perspective) crossing
the boundaries between different philosophical or scientific
disciplines. Indeed, there was no such thing as an intellectual
discipline until Aristotle invented the notion during his Lyceum period.
Aristotle divided the sciences into three kinds: productive,
practical, and theoretical. The productive sciences, naturally enough,
are those that have a product. They include not only engineering and
architecture, which have products like bridges and houses, but also
disciplines such as strategy and rhetoric, where the product is
something less concrete, such as victory on the battlefield or in the
courts. The practical sciences, most notably ethics and politics, are
those that guide behaviour. The theoretical sciences are those that have
no product and no practical goal but in which information and
understanding are sought for their own sake.
During Aristotle’s years at the Lyceum, his relationship with his
former pupil Alexander apparently cooled. Alexander became more and more
megalomaniac, finally proclaiming himself divine and demanding that
Greeks prostrate themselves before him in adoration. Opposition to this
demand was led by Aristotle’s nephew Callisthenes (c. 360–327 bc), who
had been appointed historian of Alexander’s Asiatic expedition on
Aristotle’s recommendation. For his heroism Callisthenes was falsely
implicated in a plot and executed.
When Alexander died in 323, democratic Athens became uncomfortable
for Macedonians, even those who were anti-imperialist. Saying that he
did not wish the city that had executed Socrates “to sin twice against
philosophy,” Aristotle fled to Chalcis, where he died the following
year. His will, which survives, makes thoughtful provision for a large
number of friends and dependents. To Theophrastus (c. 372–c. 287 bc),
his successor as head of the Lyceum, he left his library, including his
own writings, which were vast. Aristotle’s surviving works amount to
about one million words, though they probably represent only about
one-fifth of his total output.
Writings
Aristotle’s writings fall into two groups: those that were published by
him but are now almost entirely lost, and those that were not intended
for publication but were collected and preserved by others. The first
group consists mainly of popular works; the second group comprises
treatises that Aristotle used in his teaching.
Writings » Lost works
The lost works include poetry, letters, and essays as well as dialogues
in the Platonic manner. To judge by surviving fragments, their content
often differed widely from the doctrines of the surviving treatises. The
commentator Alexander of Aphrodisias (born c. 200) suggested that
Aristotle’s works may express two truths: an “exoteric” truth for public
consumption and an “esoteric” truth reserved for students in the Lyceum.
Most contemporary scholars, however, believe that the popular writings
reflect not Aristotle’s public views but rather an early stage of his
intellectual development.
Writings » Extant works
The works that have been preserved derive from manuscripts left by
Aristotle on his death. According to ancient tradition—passed on by
Plutarch (ad 46–c. 119) and Strabo (c. 64 bc–ad 23?)—the writings of
Aristotle and Theophrastus were bequeathed to Neleus of Scepsis, whose
heirs hid them in a cellar to prevent their being confiscated for the
library of the kings of Pergamum (in present-day Turkey). Later,
according to this tradition, the books were purchased by a collector and
taken to Athens, where they were commandeered by the Roman commander
Sulla when he conquered the city in 86 bc. Taken to Rome, they were
edited and published there about 60 bc by Andronicus of Rhodes, the last
head of the Lyceum. Although many elements of this story are
implausible, it is still widely accepted that Andronicus edited
Aristotle’s texts and published them with the titles and in the form and
order that are familiar today.
Doctrines » Logic » Syllogistic
Aristotle’s claim to be the founder of logic rests primarily on the
Categories, the De interpretatione, and the Prior Analytics, which deal
respectively with words, propositions, and syllogisms. These works,
along with the Topics, the Sophistical Refutations, and a treatise on
scientific method, the Posterior Analytics, were grouped together in a
collection known as the Organon, or “tool” of thought.
The Prior Analytics is devoted to the theory of the syllogism, a
central method of inference that can be illustrated by familiar examples
such as the following:
Every Greek is human. Every human is mortal. Therefore, every Greek
is mortal.
Aristotle discusses the various forms that syllogisms can take and
identifies which forms constitute reliable inferences. The example above
contains three propositions in the indicative mood, which Aristotle
calls “propositions.” (Roughly speaking, a proposition is a proposition
considered solely with respect to its logical features.) The third
proposition, the one beginning with “therefore,” Aristotle calls the
conclusion of the syllogism. The other two propositions may be called
premises, though Aristotle does not consistently use any particular
technical term to distinguish them.
The propositions in the example above begin with the word every;
Aristotle calls such propositions “universal.” (In English, universal
propositions can be expressed by using all rather than every; thus,
Every Greek is human is equivalent to All Greeks are human.) Universal
propositions may be affirmative, as in this example, or negative, as in
No Greek is a horse. Universal propositions differ from “particular”
propositions, such as Some Greek is bearded (a particular affirmative)
and Some Greek is not bearded (a particular negative). In the Middle
Ages it became customary to call the difference between universal and
particular propositions a difference of “quantity” and the difference
between affirmative and negative propositions a difference of “quality.”
In propositions of all these kinds, Aristotle says, something is
predicated of something else. The items that enter into predications
Aristotle calls “terms.” It is a feature of terms, as conceived by
Aristotle, that they can figure either as predicates or as subjects of
predication. This means that they can play three distinct roles in a
syllogism. The term that is the predicate of the conclusion is the
“major” term; the term of which the major term is predicated in the
conclusion is the “minor” term; and the term that appears in each of the
premises is the “middle” term.
In addition to inventing this technical vocabulary, Aristotle
introduced the practice of using schematic letters to identify
particular patterns of argument, a device that is essential for the
systematic study of inference and that is ubiquitous in modern
mathematical logic. Thus, the pattern of argument exhibited in the
example above can be represented in the schematic proposition:
If A belongs to every B, and B belongs to every C, A belongs to every
C.
Because propositions may differ in quantity and quality, and because
the middle term may occupy several different places in the premises,
many different patterns of syllogistic inference are possible.
Additional examples are the following:
Every Greek is human. No human is immortal. Therefore, no Greek is
immortal.
Some animal is a dog. Some dog is white. Therefore, every animal is
white.
From late antiquity, triads of these different kinds were called
“moods” of the syllogism. The two moods illustrated above exhibit an
important difference: the first is a valid argument, and the second is
an invalid argument, having true premises and a false conclusion. An
argument is valid only if its form is such that it will never lead from
true premises to a false conclusion. Aristotle sought to determine which
forms result in valid inferences. He set out a number of rules giving
necessary conditions for the validity of a syllogism, such as the
following:
At least one premise must be universal.
At least one premise must be affirmative.
If either premise is negative, the conclusion must be negative.
Aristotle’s syllogistic is a remarkable achievement: it is a
systematic formulation of an important part of logic. From roughly the
Renaissance until the early 19th century, it was widely believed that
syllogistic was the whole of logic. But in fact it is only a fragment.
It does not deal, for example, with inferences that depend on words such
as and, or, and if…then, which, instead of attaching to nouns, link
whole propositions together.
Doctrines » Logic » Syllogistic
Aristotle’s claim to be the founder of logic rests primarily on the
Categories, the De interpretatione, and the Prior Analytics, which deal
respectively with words, propositions, and syllogisms. These works,
along with the Topics, the Sophistical Refutations, and a treatise on
scientific method, the Posterior Analytics, were grouped together in a
collection known as the Organon, or “tool” of thought.
The Prior Analytics is devoted to the theory of the syllogism, a
central method of inference that can be illustrated by familiar examples
such as the following:
Every Greek is human. Every human is mortal. Therefore, every Greek
is mortal.
Aristotle discusses the various forms that syllogisms can take and
identifies which forms constitute reliable inferences. The example above
contains three propositions in the indicative mood, which Aristotle
calls “propositions.” (Roughly speaking, a proposition is a proposition
considered solely with respect to its logical features.) The third
proposition, the one beginning with “therefore,” Aristotle calls the
conclusion of the syllogism. The other two propositions may be called
premises, though Aristotle does not consistently use any particular
technical term to distinguish them.
The propositions in the example above begin with the word every;
Aristotle calls such propositions “universal.” (In English, universal
propositions can be expressed by using all rather than every; thus,
Every Greek is human is equivalent to All Greeks are human.) Universal
propositions may be affirmative, as in this example, or negative, as in
No Greek is a horse. Universal propositions differ from “particular”
propositions, such as Some Greek is bearded (a particular affirmative)
and Some Greek is not bearded (a particular negative). In the Middle
Ages it became customary to call the difference between universal and
particular propositions a difference of “quantity” and the difference
between affirmative and negative propositions a difference of “quality.”
In propositions of all these kinds, Aristotle says, something is
predicated of something else. The items that enter into predications
Aristotle calls “terms.” It is a feature of terms, as conceived by
Aristotle, that they can figure either as predicates or as subjects of
predication. This means that they can play three distinct roles in a
syllogism. The term that is the predicate of the conclusion is the
“major” term; the term of which the major term is predicated in the
conclusion is the “minor” term; and the term that appears in each of the
premises is the “middle” term.
In addition to inventing this technical vocabulary, Aristotle
introduced the practice of using schematic letters to identify
particular patterns of argument, a device that is essential for the
systematic study of inference and that is ubiquitous in modern
mathematical logic. Thus, the pattern of argument exhibited in the
example above can be represented in the schematic proposition:
If A belongs to every B, and B belongs to every C, A belongs to every
C.
Because propositions may differ in quantity and quality, and because
the middle term may occupy several different places in the premises,
many different patterns of syllogistic inference are possible.
Additional examples are the following:
Every Greek is human. No human is immortal. Therefore, no Greek is
immortal.
Some animal is a dog. Some dog is white. Therefore, every animal is
white.
From late antiquity, triads of these different kinds were called
“moods” of the syllogism. The two moods illustrated above exhibit an
important difference: the first is a valid argument, and the second is
an invalid argument, having true premises and a false conclusion. An
argument is valid only if its form is such that it will never lead from
true premises to a false conclusion. Aristotle sought to determine which
forms result in valid inferences. He set out a number of rules giving
necessary conditions for the validity of a syllogism, such as the
following:
At least one premise must be universal.
At least one premise must be affirmative.
If either premise is negative, the conclusion must be negative.
Aristotle’s syllogistic is a remarkable achievement: it is a
systematic formulation of an important part of logic. From roughly the
Renaissance until the early 19th century, it was widely believed that
syllogistic was the whole of logic. But in fact it is only a fragment.
It does not deal, for example, with inferences that depend on words such
as and, or, and if…then, which, instead of attaching to nouns, link
whole propositions together.
Doctrines » Logic » Propositions and categories
Aristotle’s writings show that even he realized that there is more to
logic than syllogistic. The De interpretatione, like the Prior
Analytics, deals mainly with general propositions beginning with Every,
No, or Some. But its main concern is not to link these propositions to
each other in syllogisms but to explore the relations of compatibility
and incompatibility between them. Every swan is white and No swan is
white clearly cannot both be true; Aristotle calls such pairs of
propositions “contraries.” They can, however, both be false, if—as is
the case—some swans are white and some are not. Every swan is white and
Some swan is not white, like the former pair, cannot both be true,
but—on the assumption that there are such things as swans—they cannot
both be false either. If one of them is true, the other is false; and if
one of them is false, the other is true. Aristotle calls such pairs of
propositions “contradictories.”
The propositions that enter into syllogisms are all general
propositions, whether universal or particular; that is to say, none of
them is a proposition about an individual, containing a proper name,
such as the proposition Socrates is wise. To find a systematic treatment
of singular propositions, one must turn to the Categories. This treatise
begins by dividing the “things that are said” (the expressions of
speech) into those that are simple and those that are complex. Examples
of complex sayings are A man runs, A woman speaks, and An ox drinks;
simple sayings are the particular words that enter into such complexes:
man, runs, woman, speaks, and so on. Only complex sayings can be
statements, true or false; simple sayings are neither true nor false.
The Categories identifies 10 different ways in which simple expressions
may signify; these are the categories that give the treatise its name.
To introduce the categories, Aristotle employs a heterogeneous set of
expressions, including nouns (e.g., substance), verbs (e.g., wearing),
and interrogatives (e.g., where? or how big?). By the Middle Ages it had
become customary to refer to each category by a more or less abstract
noun: substance, quantity, quality, relation, place, time, posture,
vesture, activity, and passivity.
The categories are intended as a classification of both the kinds of
expression that may function as a predicate in a proposition and of the
kinds of extralinguistic entity such expressions may signify. One might
say of Socrates, for example, that he was human (substance), that he was
five feet tall (quantity), that he was wise (quality), that he was older
than Plato (relation), and that he lived in Athens (place) in the 5th
century bc (time). On a particular occasion, his friends might have said
of him that he was sitting (posture), wearing a cloak (vesture), cutting
a piece of cloth (activity), or being warmed by the sun (passivity).
If one follows Aristotle’s lead, one will easily be able to classify
the predicates in propositions such as Socrates is potbellied and
Socrates is wiser than Meletus. But what about the term Socrates in
propositions such as Socrates is human? What category does it belong to?
Aristotle answers the question by making a distinction between “first
substance” and “second substance.” In Socrates is human, Socrates refers
to a first substance—an individual—and human to a second substance—a
species or kind. Thus, the proposition predicates the species human of
an individual, Socrates.(See below Physics and metaphysics: Form.)
Aristotle’s logical writings contain two different conceptions of the
structure of a proposition and the nature of its parts. One conception
can trace its ancestry to Plato’s dialogue the Sophist. In that work
Plato introduces a distinction between nouns and verbs, a verb being the
sign of an action and a noun being the sign of an agent of an action. A
proposition, he claims, must consist of at least one noun and at least
one verb; two nouns in succession or two verbs in succession—as in lion
stag and walks runs—will never make a proposition. The simplest kind of
proposition is something like A man learns or Theaetetus flies, and only
something with this kind of structure can be true or false. It is this
conception of a proposition as constructed from two quite heterogeneous
elements that is to the fore in the Categories and the De
interpretatione, and it is also paramount in modern logic.
In the syllogistic of the Prior Analytics, in contrast, the
proposition is conceived in quite a different way. The basic elements
out of which it is constructed are terms, which are not heterogeneous
like nouns and verbs but can occur indifferently, without change of
meaning, as either subjects or predicates. One flaw in the doctrine of
terms is that it fosters confusion between signs and what they signify.
In the proposition Every human is mortal, for example, is mortal
predicated of humans or of human? It is important to distinguish between
use and mention—between the use of a word to talk about what it
signifies and the mention of a word to talk about the word itself. This
distinction was not always easy to make in ancient Greek, because the
language lacked quotation marks. There is no doubt that Aristotle
sometimes fell into confusion between use and mention; the wonder is
that, given his dysfunctional doctrine of terms, he did not do so more
often.
Doctrines » Physics and metaphysics
Aristotle divided the theoretical sciences into three groups: physics,
mathematics, and theology. Physics as he understood it was equivalent to
what would now be called “natural philosophy,” or the study of nature
(physis; see also nature, philosophy of); in this sense it encompasses
not only the modern field of physics but also biology, chemistry,
geology, psychology, and even meteorology. Metaphysics, however, is
notably absent from Aristotle’s classification; indeed, he never uses
the word, which first appears in the posthumous catalog of his writings
as a name for the works listed after the Physics. He does, however,
recognize the branch of philosophy now called metaphysics: he calls it
“first philosophy” and defines it as the discipline that studies “being
as being.”
Aristotle’s contributions to the physical sciences are less
impressive than his researches in the life sciences. In works such as On
Generation and Corruption and On the Heavens, he presented a
world-picture that included many features inherited from his
pre-Socratic predecessors. From Empedocles (c. 490–430 bc) he adopted
the view that the universe is ultimately composed of different
combinations of the four fundamental elements of earth, water, air, and
fire. Each element is characterized by the possession of a unique pair
of the four elementary qualities of heat, cold, wetness, and dryness:
earth is cold and dry, water is cold and wet, air is hot and wet, and
fire is hot and dry. Each element has a natural place in an ordered
cosmos, and each has an innate tendency to move toward this natural
place. Thus, earthy solids naturally fall, while fire, unless prevented,
rises ever higher. Other motions of the elements are possible but are
“violent.” (A relic of Aristotle’s distinction is preserved in the
modern-day contrast between natural and violent death.)
Aristotle’s vision of the cosmos also owes much to Plato’s dialogue
Timaeus. As in that work, the Earth is at the centre of the universe,
and around it the Moon, the Sun, and the other planets revolve in a
succession of concentric crystalline spheres. The heavenly bodies are
not compounds of the four terrestrial elements but are made up of a
superior fifth element, or “quintessence.” In addition, the heavenly
bodies have souls, or supernatural intellects, which guide them in their
travels through the cosmos.
Even the best of Aristotle’s scientific work has now only a
historical interest. The abiding value of treatises such as the Physics
lies not in their particular scientific assertions but in their
philosophical analyses of some of the concepts that pervade the physics
of different eras—concepts such as place, time, causation, and
determinism.
Doctrines » Physics and metaphysics » Place
Every body appears to be in some place, and every body (at least in
principle) can move from one place to another. The same place can be
occupied at different times by different bodies, as a flask can contain
first wine and then air. So a place cannot be identical to the body that
occupies it. What, then, is place? According to Aristotle, the place of
a thing is the first motionless boundary of whatever body is containing
it. Thus, the place of a pint of wine is the inner surface of the flask
containing it—provided the flask is stationary. But suppose the flask is
in motion, perhaps on a punt floating down a river. Then the wine will
be moving too, from place to place, and its place must be given by
specifying its position relative to the motionless river banks.
As is clear from this example, for Aristotle a thing is not only in
the place defined by its immediate container but also in whatever
contains that container. Thus, all human beings are not only on the
Earth but also in the universe; the universe is the place that is common
to everything. But the universe itself is not in a place at all, since
it has no container outside it. Thus, it is clear that place as
described by Aristotle is quite different from space as conceived by
Isaac Newton (1643–1727)—as an infinite extension or cosmic grid (see
cosmos). Newtonian space would exist whether or not the material
universe had been created. For Aristotle, if there were no bodies, there
would be no place. Aristotle does, however, allow for the existence of a
vacuum, or “void,” but only if it is contained by actually existing
bodies.
Doctrines » Physics and metaphysics » The continuum
Spacial extension, motion, and time are often thought of as continua—as
wholes made up of a series of smaller parts. Aristotle develops a subtle
analysis of the nature of such continuous quantities. Two entities are
continuous, he says, when there is only a single common boundary between
them. On the basis of this definition, he seeks to show that a continuum
cannot be composed of indivisible atoms. A line, for example, cannot be
composed of points that lack magnitude. Since a point has no parts, it
cannot have a boundary distinct from itself; two points, therefore,
cannot be either adjacent or continuous. Between any two points on a
continuous line there will always be other points on the same line.
Similar reasoning, Aristotle says, applies to time and to motion.
Time cannot be composed of indivisible moments, because between any two
moments there is always a period of time. Likewise, an atom of motion
would in fact have to be an atom of rest. Moments or points that were
indivisible would lack magnitude, and zero magnitude, however often
repeated, can never add up to any magnitude.
Any magnitude, then, is infinitely divisible. But this means
“unendingly divisible,” not “divisible into infinitely many parts.”
However often a magnitude has been divided, it can always be divided
further. It is infinitely divisible in the sense that there is no end to
its divisibility. The continuum does not have an infinite number of
parts; indeed, Aristotle regarded the idea of an actually infinite
number as incoherent. The infinite, he says, has only a “potential”
existence.
Doctrines » Physics and metaphysics » Motion
Motion (kinesis) was for Aristotle a broad term, encompassing changes in
several different categories. A paradigm of his theory of motion, which
appeals to the key notions of actuality and potentiality, is local
motion, or movement from place to place. If a body X is to move from
point A to point B, it must be able to do so: when it is at A it is only
potentially at B. When this potentiality has been realized, then X is at
B. But it is then at rest and not in motion. So motion from A to B is
not simply the actualization of a potential at A for being at B. Is it
then a partial actualization of that potentiality? That will not do
either, because a body stationary at the midpoint between A and B might
be said to have partially actualized that potentiality. One must say
that motion is an actualization of a potentiality that is still being
actualized. In the Physics Aristotle accordingly defines motion as “the
actuality of what is in potentiality, insofar as it is in potentiality.”
Motion is a continuum: a mere series of positions between A and B is
not a motion from A to B. If X is to move from A to B, however, it must
pass through any intermediate point between A and B. But passing through
a point is not the same as being located at that point. Aristotle argues
that whatever is in motion has already been in motion. If X, traveling
from A to B, passes through the intermediate point K, it must have
already passed through an earlier point J, intermediate between A and K.
But however short the distance between A and J, that too is divisible,
and so on ad infinitum. At any point at which X is moving, therefore,
there will be an earlier point at which it was already moving. It
follows that there is no such thing as a first instant of motion.
Doctrines » Physics and metaphysics » Time
For Aristotle, extension, motion, and time are three fundamental
continua in an intimate and ordered relation to each other. Local motion
derives its continuity from the continuity of extension, and time
derives its continuity from the continuity of motion. Time, Aristotle
says, is the number of motion with respect to before and after. Where
there is no motion, there is no time. This does not imply that time is
identical with motion: motions are motions of particular things, and
different kinds of changes are motions of different kinds, but time is
universal and uniform. Motions, again, may be faster or slower; not so
time. Indeed, it is by the time they take that the speed of motions is
determined. Nonetheless, Aristotle says, “we perceive motion and time
together.” One observes how much time has passed by observing the
process of some change. In particular, for Aristotle, the days, months,
and years are measured by observing the Sun, the Moon, and the stars
upon their celestial travels.
The part of a journey that is nearer its starting point comes before
the part that is nearer its end. The spatial relation of nearer and
farther underpins the relation of before and after in motion, and the
relation of before and after in motion underpins the relation of earlier
and later in time. Thus, on Aristotle’s view, temporal order is
ultimately derived from the spatial ordering of stretches of motion.
Doctrines » Physics and metaphysics » Matter
Change, for Aristotle, can take place in many different categories.
Local motion, as noted above, is change in the category of place. Change
in the category of quantity is growth (or shrinkage), and change in the
category of quality (e.g., of colour) is what Aristotle calls
“alteration.” Change in the category of substance, however—a change of
one kind of thing into another—is very special. When a substance
undergoes a change of quantity or quality, the same substance remains
throughout. But does anything persist when one kind of thing turns into
another? Aristotle’s answer is yes: matter. He says,
By matter, I mean what in itself is neither of any kind nor of any
size nor describable by any of the categories of being. For it is
something of which all these things are predicated, and therefore its
essence is different from that of all the predicates.
An entity that is not of any kind, size, or shape and of which
nothing at all can be said may seem highly mysterious, but this is not
what Aristotle has in mind. His ultimate matter (he sometimes calls it
“prime matter”) is not in itself of any kind. It is not in itself of any
particular size, because it can grow or shrink; it is not in itself
water or steam, because it is both of these in turn. But this does not
mean that there is any time at which it is not of any size or any time
at which it is neither water nor steam nor anything else.
Ordinary life provides many examples of pieces of matter changing
from one kind to another. A bottle containing a pint of cream may be
found, after shaking, to contain not cream but butter. The stuff that
comes out of the bottle is the same as the stuff that went into it;
nothing has been added and nothing taken away. But what comes out is
different in kind from what went in. It is from cases such as this that
the Aristotelian notion of matter is derived.
Doctrines » Physics and metaphysics » Form
Although Aristotle’s system makes room for forms, they differ
significantly from Forms as Plato conceived them. For Aristotle, the
form of a particular thing is not separate (chorista) from the thing
itself—any form is the form of some thing. In Aristotle’s physics, form
is always paired with matter, and the paradigm examples of forms are
those of material substances.
Aristotle distinguishes between “substantial” and “accidental” forms.
A substantial form is a second substance (species or kind) considered as
a universal; the predicate human, for example, is universal as well as
substantial. Thus, Socrates is human may be described as predicating a
second substance of a first substance (Socrates) or as predicating a
substantial form of a first substance. Whereas substantial forms
correspond to the category of substance, accidental forms correspond to
categories other than substance; they are nonsubstantial categories
considered as universals. Socrates is wise, for example, may be
described as predicating a quality (wise) of a first substance or as
predicating an accidental form of a first substance. Aristotle calls
such forms “accidental” because they may undergo change, or be gained or
lost, without thereby changing the first substance into something else
or causing it to cease to exist. Substantial forms, in contrast, cannot
be gained or lost without changing the nature of the substance of which
they are predicated. In the propositions above, wise is an accidental
form and human a substantial form; Socrates could survive the loss of
the former but not the loss of the latter.
When a thing comes into being, neither its matter nor its form is
created. When one manufactures a bronze sphere, for example, what comes
into existence is not the bronze or the spherical shape but the shaped
bronze. Similarly in the case of the human Socrates. But the fact that
the forms of things are not created does not mean that they must exist
independently of matter, outside space and time, as Plato maintained.
The bronze sphere derives its shape not from an ideal Sphere but from
its maker, who introduces form into the appropriate matter in the
process of his work. Likewise, Socrates’ humanity derives not from an
ideal Human but from his parents, who introduce form into the
appropriate matter when they conceive him.
Thus, Aristotle reverses the question asked by Plato: “What is it
that two human beings have in common that makes them both human?” He
asks instead, “What makes two human beings two humans rather than one?”
And his answer is that what makes Socrates distinct from his friend
Callias is not their substantial form, which is the same, nor their
accidental forms, which may be the same or different, but their matter.
Matter, not form, is the principle of individuation.
Doctrines » Physics and metaphysics » Causation
In several places Aristotle distinguishes four types of cause, or
explanation. First, he says, there is that of which and out of which a
thing is made, such as the bronze of a statue. This is called the
material cause. Second, there is the form or pattern of a thing, which
may be expressed in its definition; Aristotle’s example is the
proportion of the length of two strings in a lyre, which is the formal
cause of one note’s being the octave of another. The third type of cause
is the origin of a change or state of rest in something; this is often
called the “efficient cause.” Aristotle gives as examples a person
reaching a decision, a father begetting a child, a sculptor carving a
statue, and a doctor healing a patient. The fourth and last type of
cause is the end or goal of a thing—that for the sake of which a thing
is done. This is known as the “final cause.”
Although Aristotle gives mathematical examples of formal causes, the
forms whose causation interests him most are the substantial forms of
living beings. In these cases substantial form is the structure or
organization of the being as a whole, as well as of its various parts;
it is this structure that explains the being’s life cycle and
characteristic activities. In these cases, in fact, formal and final
causes coincide, the mature realization of natural form being the end to
which the activities of the organism tend. The growth and development of
the various parts of a living being, such as the root of a tree or the
heart of a sheep, can be understood only as the actualization of a
certain structure for the purpose of performing a certain biological
function.
Doctrines » Physics and metaphysics » Being
For Aristotle, “being” is whatever is anything whatever. Whenever
Aristotle explains the meaning of being, he does so by explaining the
sense of the Greek verb to be. Being contains whatever items can be the
subjects of true propositions containing the word is, whether or not the
is is followed by a predicate. Thus, both Socrates is and Socrates is
wise say something about being. Every being in any category other than
substance is a property or a modification of substance. For this reason,
Aristotle says that the study of substance is the way to understand the
nature of being. The books of the Metaphysics in which he undertakes
this investigation, VII through IX, are among the most difficult of his
writings.
Aristotle gives two superficially conflicting accounts of the subject
matter of first philosophy. According to one account, it is the
discipline “which theorizes about being qua being, and the things which
belong to being taken in itself”; unlike the special sciences, it deals
with the most general features of beings, insofar as they are beings. On
the other account, first philosophy deals with a particular kind of
being, namely, divine, independent, and immutable substance; for this
reason he sometimes calls the discipline “theology.”
It is important to note that these accounts are not simply two
different descriptions of “being qua being.” There is, indeed, no such
thing as being qua being; there are only different ways of studying
being. When one studies human physiology, for example, one studies
humans qua animals—that is to say, one studies the structures and
functions that humans have in common with animals. But of course there
is no such entity as a “human qua animal.” Similarly, to study something
as a being is to study it in virtue of what it has in common with all
other things. To study the universe as being is to study it as a single
overarching system, embracing all the causes of things coming into being
and remaining in existence.
Doctrines » Physics and metaphysics » The unmoved mover
The way in which Aristotle seeks to show that the universe is a single
causal system is through an examination of the notion of movement, which
finds its culmination in Book XI of the Metaphysics. As noted above,
motion, for Aristotle, refers to change in any of several different
categories. Aristotle’s fundamental principle is that everything that is
in motion is moved by something else, and he offers a number of
(unconvincing) arguments to this effect. He then argues that there
cannot be an infinite series of moved movers. If it is true that when A
is in motion there must be some B that moves A, then if B is itself in
motion there must be some C moving B, and so on. This series cannot go
on forever, and so it must come to a halt in some X that is a cause of
motion but does not move itself—an unmoved mover.
Since the motion it causes is everlasting, this X must itself be an
eternal substance. It must lack matter, for it cannot come into
existence or go out of existence by turning into anything else. It must
also lack potentiality, for the mere power to cause motion would not
ensure the sempiternity of motion. It must, therefore, be pure actuality
(energeia). Although the revolving heavens, for Aristotle, lack the
possibility of substantial change, they possess potentiality, because
each heavenly body has the power to move elsewhere in its diurnal round.
Since these bodies are in motion, they need a mover, and this is a
motionless mover. Such a mover could not act as an efficient cause,
because that would involve a change in itself, but it can act as a final
cause—an object of love—because being loved does not involve any change
in the beloved. The stars and planets seek to imitate the perfection of
the unmoved mover by moving about the Earth in a circle, the most
perfect of shapes. For this to be the case, of course, the heavenly
bodies must have souls capable of feeling love for the unmoved mover.
“On such a principle,” Aristotle says, “depend the heavens and the world
of nature.”
Aristotle is prepared to call the unmoved mover “God.” The life of
God, he says, must be like the very best of human lives. The delight
that a human being takes in the sublimest moments of philosophical
contemplation is in God a perpetual state. What, Aristotle asks, does
God think of? He must think of something—otherwise, he is no better than
a sleeping human—and whatever he is thinking of, he must think of
eternally. Either he thinks about himself, or he thinks about something
else. But the value of a thought depends on the value of what it is a
thought of, so, if God were thinking of anything other than himself, he
would be somehow degraded. So he must be thinking of himself, the
supreme being, and his life is a thinking of thinking (noesis noeseos).
This conclusion has been much debated. Some have regarded it as a
sublime truth; others have thought it a piece of exquisite nonsense.
Among those who have taken the latter view, some have considered it the
supreme absurdity of Aristotle’s system, and others have held that
Aristotle himself intended it as a reductio ad absurdum. Whatever the
truth about the object of thought of the unmoved mover, it seems clear
that it does not include the contingent affairs of individual human
beings.
Thus, at the supreme point of Aristotle’s causal hierarchy stand the
heavenly movers, moved and unmoved, which are the final cause of all
generation and corruption. And this is why metaphysics can be called by
two such different names. When Aristotle says that first philosophy
studies the whole of being, he is describing it by indicating the field
it is to explain; when he says that it is the science of the divine, he
is describing it by indicating its ultimate principles of explanation.
Thus, first philosophy is both the science of being qua being and also
theology.
Doctrines » Philosophy of science
In his Posterior Analytics Aristotle applies the theory of the syllogism
to scientific and epistemological ends. Scientific knowledge, he urges,
must be built up out of demonstrations. A demonstration is a particular
kind of syllogism, one whose premises can be traced back to principles
that are true, necessary, universal, and immediately intuited. These
first, self-evident principles are related to the conclusions of science
as axioms are related to theorems: the axioms both necessitate and
explain the truths that constitute a science. The most important axioms,
Aristotle thought, would be those that define the proper subject matter
of a science (thus, among the axioms of geometry would be the definition
of a triangle). For this reason much of the second book of the Posterior
Analytics is devoted to definition.
The account of science in the Posterior Analytics is impressive, but
it bears no resemblance to any of Aristotle’s own scientific works.
Generations of scholars have tried in vain to find in his writings a
single instance of a demonstrative syllogism. Moreover, the whole
history of scientific endeavour contains no perfect instance of a
demonstrative science.
Doctrines » Philosophy of mind
Aristotle regarded psychology as a part of natural philosophy, and he
wrote much about the philosophy of mind. This material appears in his
ethical writings, in a systematic treatise on the nature of the soul (De
anima), and in a number of minor monographs on topics such as
sense-perception, memory, sleep, and dreams.
For Aristotle the biologist, the soul is not—as it was in some of
Plato’s writings—an exile from a better world ill-housed in a base body.
The soul’s very essence is defined by its relationship to an organic
structure. Not only humans but beasts and plants too have souls,
intrinsic principles of animal and vegetable life. A soul, Aristotle
says, is “the actuality of a body that has life,” where life means the
capacity for self-sustenance, growth, and reproduction. If one regards a
living substance as a composite of matter and form, then the soul is the
form of a natural—or, as Aristotle sometimes says, organic—body. An
organic body is a body that has organs—that is to say, parts that have
specific functions, such as the mouths of mammals and the roots of
trees.
The souls of living beings are ordered by Aristotle in a hierarchy.
Plants have a vegetative or nutritive soul, which consists of the powers
of growth, nutrition, and reproduction. Animals have, in addition, the
powers of perception and locomotion—they possess a sensitive soul, and
every animal has at least one sense-faculty, touch being the most
universal. Whatever can feel at all can feel pleasure; hence, animals,
which have senses, also have desires. Humans, in addition, have the
power of reason and thought (logismos kai dianoia), which may be called
a rational soul. The way in which Aristotle structured the soul and its
faculties influenced not only philosophy but also science for nearly two
millennia.
Aristotle’s theoretical concept of soul differs from that of Plato
before him and René Descartes (1596–1650) after him. A soul, for him, is
not an interior immaterial agent acting on a body. Soul and body are no
more distinct from each other than the impress of a seal is distinct
from the wax on which it is impressed. The parts of the soul, moreover,
are faculties, which are distinguished from each other by their
operations and their objects. The power of growth is distinct from the
power of sensation because growing and feeling are two different
activities, and the sense of sight differs from the sense of hearing not
because eyes are different from ears but because colours are different
from sounds.
The objects of sense come in two kinds: those that are proper to
particular senses, such as colour, sound, taste, and smell, and those
that are perceptible by more than one sense, such as motion, number,
shape, and size. One can tell, for example, whether something is moving
either by watching it or by feeling it, and so motion is a “common
sensible.” Although there is no special organ for detecting common
sensibles, there is a faculty that Aristotle calls a “central sense.”
When one encounters a horse, for example, one may see, hear, feel, and
smell it; it is the central sense that unifies these sensations into
perceptions of a single object (though the knowledge that this object is
a horse is, for Aristotle, a function of intellect rather than sense).
Besides the five senses and the central sense, Aristotle recognizes
other faculties that later came to be grouped together as the “inner
senses,” notably imagination and memory. Even at the purely
philosophical level, however, Aristotle’s accounts of the inner senses
are unrewarding.
At the same level within the hierarchy as the senses, which are
cognitive faculties, there is also an affective faculty, which is the
locus of spontaneous feeling. This is a part of the soul that is
basically irrational but is capable of being controlled by reason. It is
the locus of desire and passion; when brought under the sway of reason,
it is the seat of the moral virtues, such as courage and temperance. The
highest level of the soul is occupied by mind or reason, the locus of
thought and understanding. Thought differs from sense-perception and is
the prerogative, on earth, of human beings. Thought, like sensation, is
a matter of making judgments; but sensation concerns particulars, while
intellectual knowledge is of universals. Reasoning may be practical or
theoretical, and, accordingly, Aristotle distinguishes between a
deliberative and a speculative faculty.
In a notoriously difficult passage of De anima, Aristotle introduces
a further distinction between two kinds of mind: one passive, which can
“become all things,” and one active, which can “make all things.” The
active mind, he says, is “separable, impassible, and unmixed.” In
antiquity and the Middle Ages, this passage was the subject of sharply
different interpretations. Some—particularly among Arab
commentators—identified the separable active agent with God or with some
other superhuman intelligence. Others—particularly among Latin
commentators—took Aristotle to be identifying two different faculties
within the human mind: an active intellect, which formed concepts, and a
passive intellect, which was a storehouse of ideas and beliefs.
If the second interpretation is correct, then Aristotle is here
recognizing a part of the human soul that is separable from the body and
immortal. Here and elsewhere there is detectable in Aristotle, in
addition to his standard biological notion of the soul, a residue of a
Platonic vision according to which the intellect is a distinct entity
separable from the body. No one has produced a wholly satisfactory
reconciliation between the biological and the transcendent strains in
Aristotle’s thought.
Doctrines » Ethics
The surviving works of Aristotle include three treatises on moral
philosophy: the Nicomachean Ethics in 10 books, the Eudemian Ethics in 7
books, and the Magna moralia (Latin: “Great Ethics”). The Nicomachean
Ethics is generally regarded as the most important of the three; it
consists of a series of short treatises, possibly brought together by
Aristotle’s son Nicomachus. In the 19th century the Eudemian Ethics was
often suspected of being the work of Aristotle’s pupil Eudemus of
Rhodes, but there is no good reason to doubt its authenticity.
Interestingly, the Nicomachean Ethics and the Eudemian Ethics have three
books in common: books V, VI, and VII of the former are the same as
books IV, V, and VI of the latter. Although the question has been
disputed for centuries, it is most likely that the original home of the
common books was the Eudemian Ethics; it is also probable that Aristotle
used this work for a course on ethics that he taught at the Lyceum
during his mature period. The Magna moralia probably consists of notes
taken by an unknown student of such a course.
Doctrines » Ethics » Happiness
Aristotle’s approach to ethics is teleological. If life is to be worth
living, he argues, it must surely be for the sake of something that is
an end in itself—i.e., desirable for its own sake. If there is any
single thing that is the highest human good, therefore, it must be
desirable for its own sake, and all other goods must be desirable for
the sake of it. One popular conception of the highest human good is
pleasure—the pleasures of food, drink, and sex, combined with aesthetic
and intellectual pleasures. Other people prefer a life of virtuous
action in the political sphere. A third possible candidate for the
highest human good is scientific or philosophical contemplation.
Aristotle thus reduces the answers to the question “What is a good
life?” to a short list of three: the philosophical life, the political
life, and the voluptuary life. This triad provides the key to his
ethical inquiry.
“Happiness,” the term that Aristotle uses to designate the highest
human good, is the usual translation of the Greek eudaimonia. Although
it is impossible to abandon the English term at this stage of history,
it should be borne in mind that what Aristotle means by eudaimonia is
something more like well-being or flourishing than any feeling of
contentment. Aristotle argues, in fact, that happiness is activity of
the rational soul in accordance with virtue. Human beings must have a
function, because particular types of humans (e.g., sculptors) do, as do
the parts and organs of individual human beings. This function must be
unique to humans; thus, it cannot consist of growth and nourishment, for
this is shared by plants, or the life of the senses, for this is shared
by animals. It must therefore involve the peculiarly human faculty of
reason. The highest human good is the same as good human functioning,
and good human functioning is the same as the good exercise of the
faculty of reason—that is to say, the activity of rational soul in
accordance with virtue. There are two kinds of virtue: moral and
intellectual. Moral virtues are exemplified by courage, temperance, and
liberality; the key intellectual virtues are wisdom, which governs
ethical behaviour, and understanding, which is expressed in scientific
endeavour and contemplation.
Doctrines » Ethics » Virtue
People’s virtues are a subset of their good qualities. They are not
innate, like eyesight, but are acquired by practice and lost by disuse.
They are abiding states, and they thus differ from momentary passions
such as anger and pity. Virtues are states of character that find
expression both in purpose and in action. Moral virtue is expressed in
good purpose—that is to say, in prescriptions for action in accordance
with a good plan of life. It is expressed also in actions that avoid
both excess and defect. A temperate person, for example, will avoid
eating or drinking too much, but he will also avoid eating or drinking
too little. Virtue chooses the mean, or middle ground, between excess
and defect. Besides purpose and action, virtue is also concerned with
feeling. One may, for example, be excessively concerned with sex or
insufficiently interested in it; the temperate person will take the
appropriate degree of interest and be neither lustful nor frigid.
While all the moral virtues are means of action and passion, it is
not the case that every kind of action and passion is capable of a
virtuous mean. There are some actions of which there is no right amount,
because any amount of them is too much; Aristotle gives murder and
adultery as examples. The virtues, besides being concerned with means of
action and passion, are themselves means in the sense that they occupy a
middle ground between two contrary vices. Thus, the virtue of courage is
flanked on one side by foolhardiness and on the other by cowardice.
Aristotle’s account of virtue as a mean is no truism. It is a
distinctive ethical theory that contrasts with other influential systems
of various kinds. It contrasts, on the one hand, with religious systems
that give a central role to the concept of a moral law, concentrating on
the prohibitive aspects of morality. It also differs from moral systems
such as utilitarianism that judge the rightness and wrongness of actions
in terms of their consequences. Unlike the utilitarian, Aristotle
believes that there are some kinds of action that are morally wrong in
principle.
The mean that is the mark of moral virtue is determined by the
intellectual virtue of wisdom. Wisdom is characteristically expressed in
the formulation of prescriptions for action—“practical syllogisms,” as
Aristotle calls them. A practical syllogism consists of a general recipe
for a good life, followed by an accurate description of the agent’s
actual circumstances and concluding with a decision about the
appropriate action to be carried out.
Wisdom, the intellectual virtue that is proper to practical reason,
is inseparably linked with the moral virtues of the affective part of
the soul. Only if an agent possesses moral virtue will he endorse an
appropriate recipe for a good life. Only if he is gifted with
intelligence will he make an accurate assessment of the circumstances in
which his decision is to be made. It is impossible, Aristotle says, to
be really good without wisdom or to be really wise without moral virtue.
Only when correct reasoning and right desire come together does truly
virtuous action result.
Virtuous action, then, is always the result of successful practical
reasoning. But practical reasoning may be defective in various ways.
Someone may operate from a vicious choice of lifestyle; a glutton, for
example, may plan his life around the project of always maximizing the
present pleasure. Aristotle calls such a person “intemperate.” Even
people who do not endorse such a hedonistic premise may, once in a
while, overindulge. This failure to apply to a particular occasion a
generally sound plan of life Aristotle calls “incontinence.”
Doctrines » Ethics » Action and contemplation
The pleasures that are the domain of temperance, intemperance, and
incontinence are the familiar bodily pleasures of food, drink, and sex.
In treating of pleasure, however, Aristotle explores a much wider field.
There are two classes of aesthetic pleasures: the pleasures of the
inferior senses of touch and taste, and the pleasures of the superior
senses of sight, hearing, and smell. Finally, at the top of the scale,
there are the pleasures of the mind.
Plato had posed the question of whether the best life consists in the
pursuit of pleasure or the exercise of the intellectual virtues.
Aristotle’s answer is that, properly understood, the two are not in
competition with each other. The exercise of the highest form of virtue
is the very same thing as the truest form of pleasure; each is identical
with the other and with happiness. The highest virtues are the
intellectual ones, and among them Aristotle distinguished between wisdom
and understanding. To the question of whether happiness is to be
identified with the pleasure of wisdom or with the pleasure of
understanding, Aristotle gives different answers in his main ethical
treatises. In the Nicomachean Ethics perfect happiness, though it
presupposes the moral virtues, is constituted solely by the activity of
philosophical contemplation, whereas in the Eudemian Ethics it consists
in the harmonious exercise of all the virtues, intellectual and moral.
The Eudemian ideal of happiness, given the role it assigns to
contemplation, to the moral virtues, and to pleasure, can claim to
combine the features of the traditional three lives—the life of the
philosopher, the life of the politician, and the life of the pleasure
seeker. The happy person will value contemplation above all, but part of
his happy life will consist in the exercise of moral virtues in the
political sphere and the enjoyment in moderation of the natural human
pleasures of body as well as of soul. But even in the Eudemian Ethics it
is “the service and contemplation of God” that sets the standard for the
appropriate exercise of the moral virtues, and in the Nicomachean Ethics
this contemplation is described as a superhuman activity of a divine
part of human nature. Aristotle’s final word on ethics is that, despite
being mortal, human beings must strive to make themselves immortal as
far as they can.
Doctrines » Political theory
Turning from the Ethics treatises to their sequel, the Politics, the
reader is brought down to earth. “Man is a political animal,” Aristotle
observes; human beings are creatures of flesh and blood, rubbing
shoulders with each other in cities and communities. Like his work in
zoology, Aristotle’s political studies combine observation and theory.
He and his students documented the constitutions of 158 states—one of
which, The Constitution of Athens, has survived on papyrus. The aim of
the Politics, Aristotle says, is to investigate, on the basis of the
constitutions collected, what makes for good government and what makes
for bad government and to identify the factors favourable or
unfavourable to the preservation of a constitution.
Aristotle asserts that all communities aim at some good. The state
(polis), by which he means a city-state such as Athens, is the highest
kind of community, aiming at the highest of goods. The most primitive
communities are families of men and women, masters and slaves. Families
combine to make a village, and several villages combine to make a state,
which is the first self-sufficient community. The state is no less
natural than the family; this is proved by the fact that human beings
have the power of speech, the purpose of which is “to set forth the
expedient and inexpedient, and therefore likewise the just and the
unjust.” The foundation of the state was the greatest of benefactions,
because only within a state can human beings fulfill their potential.
Government, Aristotle says, must be in the hands of one, of a few, or
of the many; and governments may govern for the general good or for the
good of the rulers. Government by a single person for the general good
is called “monarchy”; for private benefit, “tyranny.” Government by a
minority is “aristocracy” if it aims at the state’s best interest and
“oligarchy” if it benefits only the ruling minority. Popular government
in the common interest Aristotle calls “polity”; he reserves the word
“democracy” for anarchic mob rule.
If a community contains an individual or family of outstanding
excellence, then, Aristotle says, monarchy is the best constitution. But
such a case is very rare, and the risk of miscarriage is great, for
monarchy corrupts into tyranny, which is the worst constitution of all.
Aristocracy, in theory, is the next-best constitution after monarchy
(because the ruling minority will be the best-qualified to rule), but in
practice Aristotle preferred a kind of constitutional democracy, for
what he called “polity” is a state in which rich and poor respect each
other’s rights and the best-qualified citizens rule with the consent of
all.
Two elements of Aristotle’s teaching affected European political
institutions for many centuries: his justification of slavery and his
condemnation of usury. Some people, Aristotle says, think that the rule
of master over slave is contrary to nature and therefore unjust. But
they are quite wrong: a slave is someone who is by nature not his own
property but someone else’s. Aristotle agrees, however, that in practice
much slavery is unjust, and he speculates that, if nonliving machines
could be made to carry out menial tasks, there would be no need for
slaves as living tools. Nevertheless, some people are so inferior and
brutish that it is better for them to be controlled by a master than to
be left to their own devices.
Although not himself an aristocrat, Aristotle had an aristocratic
disdain for commerce. Our possessions, he says, have two uses, proper
and improper. Money too has a proper and an improper use; its proper use
is to be exchanged for goods and services, not to be lent out at
interest. Of all the methods of making money, “taking a breed from
barren metal” is the most unnatural.
Doctrines » Rhetoric and poetics
Rhetoric, for Aristotle, is a topic-neutral discipline that studies the
possible means of persuasion. In advising orators on how to exploit the
moods of their audience, Aristotle undertakes a systematic and often
insightful treatment of human emotion, dealing in turn with anger,
hatred, fear, shame, pity, indignation, envy, and jealousy—in each case
offering a definition of the emotion and a list of its objects and
causes.
The Poetics is much better known than the Rhetoric, though only the
first book of the former, a treatment of epic and tragic poetry,
survives. The book aims, among other things, to answer Plato’s
criticisms of representative art. According to the theory of Forms,
material objects are imperfect copies of original, real, Forms; artistic
representations of material objects are therefore only copies of copies,
at two removes from reality. Moreover, drama has a specially corrupting
effect, because it stimulates unworthy emotions in its audience. In
response, Aristotle insists that imitation, so far from being the
degrading activity that Plato describes, is something natural to humans
from childhood and is one of the characteristics that makes humans
superior to animals, since it vastly increases the scope of what they
may learn.
In order to answer Plato’s complaint that playwrights are only
imitators of everyday life, which is itself only an imitation of the
real world of Forms, Aristotle draws a contrast between poetry and
history. The poet’s job is to describe not something that has actually
happened but something that might well happen—that is to say, something
that is possible because it is necessary or likely. For this reason,
poetry is more philosophical and more important than history, for poetry
speaks of the universal, history of only the particular. Much of what
happens to people in everyday life is a matter of sheer accident; only
in fiction can one witness character and action work themselves out to
their natural consequences.
Far from debasing the emotions, as Plato thought, drama has a
beneficial effect on them. Tragedy, Aristotle says, must contain
episodes arousing pity and fear so as to achieve a “purification” of
these emotions. No one is quite sure exactly what Aristotle meant by
katharsis, or purification. But perhaps what he meant was that watching
tragedy helps people to put their own sorrows and worries in
perspective, because in it they observe how catastrophe can overtake
even people who are vastly their superiors.
Legacy
Since the Renaissance it has been traditional to regard the Academy and
the Lyceum as two opposite poles of philosophy. Plato is idealistic,
utopian, otherworldly; Aristotle is realistic, utilitarian,
commonsensical. (This viewpoint is reflected in the famous depiction of
Plato and Aristotle in Raphael’s Vatican fresco The School of Athens.)
In fact, however, the doctrines that Plato and Aristotle share are more
important than those that divide them. Many post-Renaissance historians
of ideas have been less perceptive than the commentators of late
antiquity, who saw it as their duty to construct a harmonious concord
between the two greatest philosophers of the known world.
By any reckoning, Aristotle’s intellectual achievement is stupendous.
He was the first genuine scientist in history. He was the first author
whose surviving works contain detailed and extensive observations of
natural phenomena, and he was the first philosopher to achieve a sound
grasp of the relationship between observation and theory in scientific
method. He identified the various scientific disciplines and explored
their relationships to each other. He was the first professor to
organize his lectures into courses and to assign them a place in a
syllabus. His Lyceum was the first research institute in which a number
of scholars and investigators joined in collaborative inquiry and
documentation. Finally, and not least important, he was the first person
in history to build up a research library, a systematic collection of
works to be used by his colleagues and to be handed on to posterity.
Millennia later, Plato and Aristotle still have a strong claim to
being the greatest philosophers who have ever lived. But if their
contribution to philosophy is equal, it was Aristotle who made the
greater contribution to the intellectual patrimony of the world. Not
only every philosopher but also every scientist is in his debt. He
deserves the title Dante gave him: “the master of those who know.”
Sir Anthony J.P. Kenny
Encyclopaedia Britannica