Aristotle of Stagira is one of the two most important philosophers of the ancient world, and one of the four or five most important of any time or place. He was not an Athenian, but he spent most of his life as a student and teacher of philosophy in Athens. For twenty years he was a member of Plato’s Academy; later he set up his own philosophical school, the Lyceum. During his lifetime he published philosophical dialogues, of which only fragments now survive. The ‘Aristotelian corpus’ (1462 pages of Greek text, including some spurious works) is probably derived from the lectures that he gave in the Lyceum.
Aristotle is the founder not only of philosophy as a discipline with distinct areas or branches, but, still more generally, of the conception of intellectual inquiry as falling into distinct disciplines. He insists, for instance, that the standards of proof and
evidence for deductive logic and mathematics should not be applied to the study of nature, and that neither of these disciplines should be taken as a proper model for moral and political inquiry. He distinguishes philosophical reflection on a discipline from the practice of the discipline itself. The corpus contains contributions to many different disciplines, not only to philosophy.
Some areas of inquiry in which Aristotle makes a fundamental contribution are these:
(1) Logic. Aristotle’s Prior Analytics constitutes the first attempt to formulate a system of deductive formal logic, based on the theory of the ‘syllogism’. The Posterior Analytics uses this system to formulate an account of rigorous scientific knowledge. ‘Logic’, as Aristotle conceives it, also includes the study of language, meaning and their relation to
non-linguistic reality; hence it includes many topics that might now be assigned to philosophy of language or philosophical logic (Categories, De Interpretatione, Topics).
(2) The study of nature. About a quarter of the corpus (see especially the History of Animals, Parts of Animals, and Generation of Animals; also Movement of Animals, Progression of Animals) consists of works concerned with biology. Some of these contain collections of detailed observations. (The Meteorology contains a similar collection on inanimate nature.) Others try to explain these observations in the light of the explanatory scheme that Aristotle defends in his more theoretical reflections on the study of nature. These reflections (especially in the Physics and in Generation and Corruption) develop an account of nature, form, matter, cause and change that expresses Aristotle’s views about the understanding and explanation of natural organisms and their behaviour. Natural philosophy and cosmology are combined in On the Heavens.
(3) Metaphysics. In his reflections on the foundations and presuppositions of other disciplines, Aristotle describes a universal ‘science of being qua being’, the concern of the Metaphysics. Part of this universal science examines the foundations of inquiry into nature. Aristotle formulates his doctrine of substance, which he explains through the connected contrasts between form and matter, and between potentiality and actuality. One of his aims is to describe the distinctive and irreducible character of living organisms. Another aim of the universal science is to use his examination of substance to give an account of divine substance, the ultimate principle of the cosmic order.
(4) Philosophy of mind. The doctrine of form and matter is used to explain the relation of soul and body, and the different types of soul found in different types of living creatures. In Aristotle’s view, the soul is the form of a living body. He examines the different aspects of this form in plants, non-rational animals and human beings, by describing nutrition, perception, thought and desire. His discussion (in On the Soul, and also in the Parva Naturalia) ranges over topics in philosophy of mind, psychology, physiology, epistemology and theory of action.
(5) Ethics and politics (Nicomachean Ethics, Eudemian Ethics, Magna Moralia). In Aristotle’s view, the understanding of the natural and essential aims of human agents is the right basis for a grasp of principles guiding moral and political practice. These principles are expressed in his account of human wellbeing, and of the different virtues that constitute a good person and promote wellbeing. The description of a society that embodies these virtues in individual and social life is a task for the Politics, which also examines the virtues and vices of actual states and societies, measuring them against the
principles derived from ethical theory.
(6) Literary criticism and rhetorical theory (Poetics, Rhetoric). These works are closely connected both to Aristotle’s logic and to his ethical and political theory.
Aristotle was born in 384 BC, in the Macedonian city of Stagira, now part of northern Greece. In his lifetime the kingdom of Macedon, first under Philip and then under Philip’s son Alexander (‘the Great’), conquered both the Greek cities of Europe and Asia and the Persian Empire. Although Aristotle spent much of his adult life in Athens, he was not an Athenian citizen. He was closely linked to the kings of Macedon, whom many Greeks regarded as foreign invaders; hence, he was affected by the volatile relations between Macedon and the Greek cities, especially Athens.
Aristotle was the son of Nicomachus, a doctor attached to the Macedonian court. In 367 BC Aristotle came to Athens. He belonged to Plato’s Academy until the death of Plato in 347; during these years Plato wrote his important later dialogues (including the Sophist, Timaeus, Philebus, Statesman, and Laws), which reconsider many of the doctrines of his earlier dialogues and pursue new lines of thought. Since there was no dogmatic system of ‘Platonism’, Aristotle was neither a disciple of such a system nor a rebel against it. The exploratory and critical outlook of the Academy probably encouraged Aristotle’s own philosophical growth.
In 347 BC Aristotle left Athens, for Assos in Asia Minor. Later he moved to Lesbos, in the eastern Aegean, and then to Macedon, where he was a tutor of Alexander. In 334 he returned to Athens and founded his own school, the Lyceum. In 323 Alexander died; in the resulting outbreak of anti-Macedonian feeling in Athens Aristotle left for Chalcis, on the island of Euboea, where he died in 322.
Aristotle married Pythias, a niece of Hermeias, the ruler of Assos. They had a daughter, also called Pythias. After the death of his wife, Aristotle formed an attachment to Herpyllis, and they had a son Nicomachus.
2 Order of Aristotle’s works By the end of Aristotle’s life the Lyceum must have become a well-established school. It lasted after Aristotle’s death; his successor as head of the school was his pupil Theophrastus. Many of the works in the Aristotelian corpus appear to be closely related to Aristotle’s lectures in the Lyceum. The polished character of some passages suggests preparation for publication (for example, Parts of Animals I 5), but many passages contain incomplete sentences and compressed allusions, suggesting notes that a lecturer might expand (for example, Metaphysics VII 13). We cannot tell how many of his treatises Aristotle regarded as ‘finished’ (see §11 on the Metaphysics and §21 on the Ethics).
It may be wrong, therefore, to ask about the ‘date’ of a particular treatise. If Aristotle neither published nor intended to publish the treatises, a given treatise may easily contain contributions from different dates. For similar reasons, we cannot plausibly take cross-references from one work to another as evidence of the order of the works. External, biographical considerations are unhelpful, since we lack the evidence to support any detailed intellectual biography of Aristotle.
A few points, however, may suggest a partial chronology.
(1) Some of Aristotle’s frequent critical discussions of Plato and other Academics may have been written (in some version) during Aristotle’s years in the Academy. The Topics may reflect the character of dialectical debates in the Academy.
(2) It is easier to understand the relation of the doctrine of substance in the Categories and Physics I-II to the doctrine and argument of MetaphysicsVII if we suppose that Metaphysics VII is later.
(3) The Organon (see §4) does not mention matter, perhaps because (a) Aristotle had not yet thought of it, or because (b) he regarded it as irrelevant to the topics considered in the Organon. If (a) is correct, the Organon precedes the works on natural philosophy.
(4) Some of the observations used in Aristotle’s biological works probably came from the eastern Aegean. Hence, Aristotle probably pursued his biological research during his years away from Athens. We might trace his biological interests to the Academy (see Plato’s Timaeus); he may also have acquired them from his father Nicomachus, who was a doctor. Probably, then, at least some of the biological works (or versions of them) are not the latest works in the corpus.
(5) The Magna Moralia (if it is genuine) and the Eudemian Ethics probably precede the Nicomachean Ethics (see §21).
The order in which Aristotle’s works appear in the Greek manuscripts goes back to early editors and commentators (from the first century BC to the sixth century AD); it reflects their view not about the order in which the works were written, but about the order in which they should be studied. This entry generally follows the order of the corpus, except that it discusses On the Soul after the Metaphysics (see §17), not among the works on natural philosophy (where it appears in the manuscripts).
3 Appearances The general aim of rational inquiry, according to Aristotle, is to advance from what is ‘better known to us’ to what is ‘better known by nature’ (see Physics I 1; Posterior Analytics 71b33; Metaphysics 1029b3). We achieve this aim if: (1) we replace propositions that we thought we knew with propositions that we really know because they are true and we understand them; (2) we find general principles that explain and justify the more specific truths that we began from; (3) we find those aspects of reality that explain the aspects that are more familiar to us.
The things better known to us in a particular area are the relevant ‘appearances’ (phainomena). Aristotle presents them through detailed collections of empirical data, reached as a result of ‘inquiry’ (historia; for example, Parts of Animals 646a8). Empirical inquiry proceeds from particular observations, by means of generalizations through induction from these particular cases, until we reach experience. Experience leads us to principles that are better known by nature (Prior Analytics 46a17); we also rely on it to test principles we have found (Generation of Animals 760b28).
Philosophical inquiry also relies on ‘appearances’. However, the appearances that concern it are not empirical observations, but common beliefs, assumptions widely shared by ‘the many and the wise’. The critical and constructive study of these common beliefs is ‘dialectic’. Aristotle’s method is basically Socratic. He raises puzzles in the common beliefs, looking for an account that will do them justice as a whole. Among common beliefs Aristotle considers the views of his predecessors (for example, Metaphysics I; On the Soul I; Politics II), because the puzzles raised by their views help us to find better solutions than they found.
Inquiry leads us to causes and to universals. Aristotle has a realist conception of inquiry and knowledge; beliefs and theories are true in so far as they grasp the reality that we inquire into. Universals and causes are ‘prior by nature’; they are not created by, or dependent on, any theory, but a true theory must fit them.
If we attended only to Aristotle’s remarks on what is better known to us and on the process of inquiry, we might regard his position as a form of empiricism. But in his remarks on what is better known by nature, he insists on the reality of universals and on the importance of non-sensory forms of knowledge (see §15 on universals, §19 on thought).
4 Thought and language One means of access to appearances, and especially to common beliefs, is the study of what words and sentences ‘signify’. This is part of ‘logic’ (derived from logos, which may be translated ‘word’, ‘speech’, ‘statement’, ‘argument’ or ‘reason’), which is discussed in the first section of Aristotle’s works (Categories, De Interpretatione, Prior Analytics, Posterior Analytics, Topics). This section of the corpus came to be called the ‘Organon’ (‘instrument’), because logic, as Aristotle conceives it, concerns statements and arguments in general, without restriction to any specific subject matter; it is therefore an instrument of philosophical inquiry in general, rather than a branch of philosophy coordinate with natural philosophy or ethics. The Organon includes some elements of philosophy of language, as well as formal logic (syllogistic; see §5) and epistemology (see §6).
According to Aristotle’s account of signification (see especially De Interpretatione 1-4), as commonly understood, the word ‘horse’ signifies horse by signifying the thought of horse; in using the word, we communicate thoughts about horses. When the thoughts about horses we communicate are true, we communicate truths about the universal horse; even when our thoughts are not completely true, we may signify the same universal horse.
To understand the signification of a name ‘F’, we look for the corresponding definition (logos, horismos) of F. Aristotle distinguishes nominal definitions, stating the beliefs associated with the name, from real definitions, giving a true account of the universal that underlies the beliefs embodied in the nominal definition (see Posterior Analytics II 8-10. Aristotle himself does not use the labels ‘nominal definition’ and ‘real definition’.).
Not every name corresponds to one nominal and one real definition. Some names correspond to no genuine universal; ‘goatstag’ signifies (in one way) animals that are both goats and stags, but it does not signify a genuine universal, since there is no natural kind of goatstag. Other names correspond to more than one universal, as ‘chest’ signifies both a container and a part of an animal. Chests are ‘homonymous’ or ‘multivocal’ (‘spoken of in many ways’); more than one definition is needed to capture the signification of the name. By contrast, since only one definition corresponds to the name ‘horse’, horses are ‘synonymous’ (Categories 1).
Other philosophers make serious errors, Aristotle believes, because they suppose they can give a single account of things or properties that are really multivocal. Once we see that different Fs are F in different ways, we see that different, although (in many cases) connected, accounts of what it is to be F must be given. Some philosophically important cases of multivocity are cause (Aristotle’s doctrine of the four causes; see §9), being (the doctrine of the categories; see §7) and good (the criticism of Plato’s belief in a Form of the Good; Nicomachean Ethics I 6).