Theophrastus, the successor of Aristotle in the Peripatetic school, a native of Eresus in Lesbos, was born c. 372 BC. His original name was Tyrtamus, but he later became known by the nickname "Theophrastus," given to him, it is said, by Aristotle to indicate the grace of his conversation.

After receiving his first introduction to philosophy in Lesbos from one Leucippus or Alcippus, he proceeded to Athens, and became a member of the Platonic circle. After Plato's death he attached himself to Aristotle, and in all probability accompanied him to Stagira. The intimate friendship of Theophrastus with Callisthenes, the fellow-pupil of Alexander the Great, the mention made in his will of an estate belonging to him at Stagira, and the repeated notices of the town and its museum in the History of Plants, are facts which point to this conclusion.

Aristotle in his will made him guardian of his children, bequeathed to him his library and the originals of his works, and designated him as his successor at the Lyceum on his own removal to Chalcis. Eudemus of Rhodes also had some claims to this position, and Aristoxenus is said to have resented Aristotle's choice.

Theophrastus presided over the Peripatetic school for thirty-five years, and died in 287 BC. Under his guidance the school flourished greatly--there were at one period more than 2000 students--and at his death he bequeathed to it his garden with house and colonnades as a permanent seat of instruction. Menander was among his pupils. His popularity was shown in the regard paid to him by Philip, Cassander and Ptolemy, and by the complete failure of a charge of impiety brought against him. He was honoured with a public funeral, and "the whole population of Athens, honouring him greatly, followed him to the grave" (Diog. Laërt.).

From the lists of the ancients it appears that the activity of Theophrastus extended over the whole field of contemporary knowledge. His writing probably differed little from the Aristotelian treatment of the same themes, though supplementary in details. He served his age mainly as a great popularizer of science. The most important of his books are two large botanical treatises, On the History of Plants, in nine books (originally ten), and On the Causes of Plants, in six books (originally eight), which constitute the most important contribution to botanical science during antiquity and the middle ages. We also possess in fragments a History of Physics, a treatise On Stones, and a work On Sensation, and certain metaphysical Airoptai, which probably once formed part of a systematic treatise. Various smaller scientific fragments have been collected in the editions of JG Schneider (1818-21) and F Wimmer (1842-62) and in Usener's Analecta Theophrastea.

The Ethical Characters deserves a separate mention. The work consists of brief, vigorous and trenchant delineations of moral types, which contain a most valuable picture of the life of his time. They form the first recorded attempt at systematic character writing. The book has been regarded by some as an independent work; others incline to the view that the sketches were written from time to time by Theophrastus, and collected and edited after his death; others, again, regard the Characters as part of a larger systematic work, but the style of the book is against this. Theophrastus has found many imitators in this kind of writing, notably Hall (1608), Sir Thomas Overbury (1614-16), Bishop Earle (1628) and Jean de La Bruyère (1688), who also translated the Characters.

This article incorporates text from the public domain 1911 Encyclopædia Britannica.