PERIPATETICS (from Gr. περιπατεῖν, to walk about), the name given in antiquity to the followers of Aristotle (q.v.), either from his habit of walking up and down as he lectured to his pupils, or from the περίπατος (covered walk) of the Lyceum.

Aristotle’s immediate successors,[1] Theophrastus and Eudemus of Rhodes, were diligent scholars rather than original thinkers. They made no innovations upon the main doctrines of their master, and their industry is chiefly directed to supplementing his works in minor particulars. Thus they amplified the Aristotelian logic by the theory of the Theophrastus. hypothetical and disjunctive syllogism, and added to the first figure of the categorical syllogism the five moods out of which the fourth figure was afterwards constructed. The impulse towards natural science and the systematizing of empirical details which distinguished Aristotle from Plato was shared by Theophrastus (q.v.). The same turn for detail is observable in his ethics, where, to judge from the imperfect evidence of the Characters, he elaborated still farther Aristotle’s portraiture of the virtues and their relative vices. In his doctrine of virtue the distinctive Peripatetic position regarding the importance of external goods was defended by him with emphasis against the assaults of the Stoics. He appears to have laid even more stress on this point than Aristotle himself, being doubtless led to do so, partly by the heat of controversy and partly by the importance which leisure and freedom from harassing cares naturally assumed to a man of his studious temperament. The metaphysical ἀπορίαι of Theophrastus which have come down to us show that he was fully alive to the difficulties that beset many of the Aristotelian definitions. But we are ignorant how he proposed to meet his own criticisms, and they do not appear to have suggested to him an actual departure from his master's doctrine, much less any radical transformation of it. In the difficulties which he raises we may perhaps detect a leaning towards a naturalistic interpretation. The tendency of Eudemus, Eudemus of Rhodes. on the other hand, is more towards the theological or Platonic side of Aristotles philosophy. The Eudemian Ethics (which, with the possible exception of the three books common to this treatise and the Nicomachean Ethics, there need be no hesitation in ascribing to Eudemus) expressly identify Aristotle's ultimate ethical ideal of θεωρία with the knowledge and contemplation of God. And this supplies Eudemus with a standard for the determination of the mean by reason, which Aristotle demanded, but himself left vague. Whatever furthers us in our progress towards a knowledge of God is good, every hindrance is evil. The same spirit may be traced in the author of the chapters which appear as an appendix to book i. of Aristotle's Metaphysics. They have been attributed to Pasicles, the nephew of Eudemus. For the rest, Eudemus shows even less philosophical independence than Theophrastus. Among the Peripatetics of the first generation who had been personal disciples of Aristotle, the other chief names are those of Aristoxenus (q.v.) of Tarentum and Dicaearchus (q.v.) of Messene. Aristoxenus, who had formerly belonged to the Pythagorean school, maintained the position, already combated by Plato in the Phaedo, that the soul is to be regarded as nothing more than the harmony of the body. Dicaearchus agreed with his friend in this naturalistic rendering of the Aristotehan entelechy, and is recorded to have argued formally against the immortality of the soul.

The naturalistic tendency of the school reached its full expression in Strato of Lampsacus, the most independent, and Strato of Lampsacus. probably the ablest, of the earlier Peripatetics. His system is based upon the formal denial of a transcendent deity. Cicero attributes to him the saying that he did not require the aid of the gods in the construction of the universe; in other words, he reduced the formation of the world to the operation of natural forces. We have evidence that he did not substitute an immanent world-soul for Aristotle's extra-mundane deity, he recognized nothing beyond natural necessity. He was at issue, however, with the atomistic materialism of Democritus in regard to its twin assumptions of absolute atoms and infinite space. His own speculations led him rather to lay stress on the qualitative aspect of the world. The true explanation of things was to be found, according to Strato, in the forces which produced their attributes, and he followed Aristotle in deducing all phenomena from the fundamental attributes or elements of heat and cold. His psychological doctrine explained all the functions of the soul as modes of motion, and denied any separation of the reason from the faculties of sense-perception. He appealed in this connexion to the statement of Aristotle that we are unable to think without a sense-image.

The successors of Strato in the headship of the Lyceum were Lyco, Aristo of Ceos, Critolaus (q.v.), Diodorus of Tyre, and Erymneus, who brings the philosophic succession down to about 100 B.C. Other Peripatetics belonging to this period are Hieronymus of Rhodes, Prytanis and Phormio of Ephesus, the delirus senex who attempted to instruct Hannibal in the art of war (Cic. De orat. ii. 18). Sotion, Hermippus and Satyrus were historians rather than philosophers. Heraclides Lembus, Agatharchides and Antisthenes of Rhodes are names to us and nothing more. The fact is that, after Strato, the Peripatetic school has no thinker of any note for about 200 years.

Early in the 1st century B.C. all the philosophic schools began to be invaded by a spirit of eclecticism. This was partly due to the influence of the practical Roman spirit. This influence is illustrated by the proconsul Lucius Gellius Publicola (about 70 B.C.), who proposed to the representatives of the schools in Athens that he should help them to settle their differences (Cic. De leg. i. 20). This atmosphere of indifference imperceptibly influenced the attitude of the contending schools to one another, and we find various movements towards unity in the views of Boethus the Stoic, Panaetius and Antiochus of Ascalon, founder of the so-called “Fifth Academy.” Meanwhile the Peripatetic school may be said to have taken a new departure and a new lease of life. The impulse was due to Andronicus of Rhodes. His critical edition of Aristotle indicated to the Andronicus. later Peripatetics the direction in which they could profitably work, and the school devoted itself henceforth almost exclusively to the writing of commentaries on Aristotle, e.g. those of Boethus of Sidon, Aristo of Alexandria, Staseas, Cratippus, and Nicolaus of Damascus. The most interesting Peripatetic work of the period is the treatise De mundo, which is a good example within the Peripatetic school of the eclectic tendency which was then in the air. The admixture of Stoic elements is so great that some critics have attributed the work to a Stoic author; but the writer's Peripateticism seems to be the more fundamental constituent of his doctrine.

Our knowledge of the Peripatetic school during the first two centuries of the Christian era is very fragmentary; but those of its representatives of whom anything is known confined themselves entirely to commenting upon the different treatises of Aristotle. Thus Alexander of Aegae, the teacher of Nero, commented on the Categories and the De caelo. In the 2nd century Aspasius (q.v.) and Adrastus of Aphrodisias wrote numerous commentaries. The latter also treated of the order of the Aristotelian writings in a separate work. Somewhat later, Herminus, Achaicus and Sosigenes commented on the logical treatises. Aristocles of Messene, the teacher of Alexander of Aphrodisias, was the author of a complete critical history of Greek philosophy. This second phase of the activity of the school closes with the comprehensive labours of Alexander of Aphrodisias (Scholarch, c. 200), the exegete par excellence, called sometimes the second Aristotle. Alexander's interpretation proceeds throughout upon the Alexander of Aphrodisias. naturalistic lines which have already become familiar to us. Aristotle had maintained that the individual alone is real, and had nevertheless asserted that the universal is the proper object of knowledge. Alexander seeks consistency by holding to the first position alone. The individual is prior to the universal, he says, not only “for us,” but also in itself, and universals are abstractions which have merely a subjective existence in the intelligence which abstracts them Even the deity must be brought under the conception of individual substance. Such an interpretation enables us to understand how it was possible, at a later date, for Aristotle to be regarded as the father of Nominalism. Form, Alexander proceeds, is everywhere indivisible from matter. Hence the soul is inseparable from the body whose soul or form it is. Reason or intellect is bound up with the other faculties. Alexander's commentaries formed the foundation of the Arabian and Scholastic study of Aristotle. Soon after Alexander's death the Peripatetic school was merged, like all others, in Neoplatonism (q.v.).

  1. See Gellius, Noct. Att. xiii. 5, for the story of how Aristotle chose Theophrastus as his successor.