Theophrastus (ˌθiː.əˈfræstəs; ; 371 - 287 BC) was a Greek philosopher and the successor to Aristotle in the Peripatetic school. He was a native of Eresos in Lesbos. His given name was Τύρταμος (); his nickname Θεόφραστος () was given by Aristotle, his teacher, for his "divine style of expression".
He came to Athens at a young age and initially studied in Plato's school. After Plato's death, he attached himself to Aristotle who took to Theophrastus in his writings. When Aristotle fled Athens, Theophrastus took over as head of the Lyceum. Theophrastus presided over the Peripatetic school for thirty-six years, during which time the school flourished greatly. He is often considered the father of botany for his works on plants. After his death, the Athenians honoured him with a public funeral. His successor as head of the school was Strato of Lampsacus.
The interests of Theophrastus were wide ranging, including biology, physics, ethics and metaphysics. His two surviving botanical works, Enquiry into Plants (Historia Plantarum) and On the Causes of Plants, were an important influence on Renaissance science. There are also surviving works On Moral Characters, On Sense Perception, and On Stones, as well as fragments on Physics and Metaphysics. In philosophy, he studied grammar and language and continued Aristotle's work on logic. He also regarded space as the mere arrangement and position of bodies, time as an accident of motion, and motion as a necessary consequence of all activity. In ethics, he regarded happiness as depending on external influences as well as on virtue.
Most of the biographical information about Theophrastus was provided by Diogenes Laërtius' Lives and Opinions of Eminent Philosophers, written more than four hundred years after Theophrastus's time. He was a native of Eresos in Lesbos. His given name was Tyrtamus (Τύρταμος), but he later became known by the nickname "Theophrastus", given to him, it is said, by Aristotle to indicate the grace of his conversation (from Ancient Greek Θεός 'god' and φράζειν 'to phrase', i.