Aristotle (384 - 322 BC)

Just as Plato had been a pupil of Socrates, so Aristotle was a pupil of Plato and Aristotle himself became a  tutor of Alexander the Great. So, there is direct line of intellectual succession here through four generations of tremendous historical importance.
Aristotle was  born in the city of Stagira, Chalkidice, on the northern periphery of Classical Greece. Aristotle's father , Nicomachus, was a court Physician to the King of Macedonwhich paves the way of his becoming tutor of Alexander, son of Philip of Macedon.His father died when he was a boy . He was brought up by a guardian, 

Proxenus of Atarneus, who sent him to Athens when he was about 17. Aristotle stayed at the Academy for something like 20 years. Later he founded a school in 355 of his own in Athens called Lyceum its archaeological site was recently discovered with great excitement in 1996.

Plato (left) and Aristotle (right), a detail of The School of Athens, a fresco by Raphael. Aristotle gestures to the earth, representing his belief in knowledge through empirical observation and experience, while holding a copy of hisNicomachean Ethics in his hand, whilst Plato gestures to the heavens, representing his belief in The Forms, while holding a copy of Timaeus. 

School of Aristotle in Mieza,Macedonia, Greece

Aristotle, whose name means "the best purpose", was born in 384 BC in Stagira, Chalcidice, about 55 km (34 miles) east of modern-day Thessaloniki. His father Nicomachus was the personal physician to King Amyntas of Macedon. Although there is little information on Aristotle's childhood, he probably spent some time within the Macedonian palace, making his first connections with the Macedonian monarchy.

At about the age of eighteen, Aristotle moved to Athens to continue his education at Plato's Academy. He remained there for nearly twenty years before leaving Athens in 348/47 BC. The traditional story about his departure records that he was disappointed with the Academy's direction after control passed to Plato's nephew Speusippus, although it is possible that he feared anti-Macedonian sentiments and left before Plato died.

"Aristotle" by Francesco Hayez (1791–1882)

Aristotle then accompanied Xenocrates to the court of his friend Hermias of Atarneus in Asia Minor. There, he traveled with Theophrastus to the island of Lesbos, where together they researched the botany and zoology of the island. Aristotle married Pythias, either Hermias's adoptive daughter or niece. She bore him a daughter, whom they also named Pythias. Soon after Hermias' death, Aristotle was invited by Philip II of Macedon to become the tutor to his son Alexander in 343 BC.

Aristotle was appointed as the head of the royal academy of Macedon. During that time he gave lessons not only to Alexander, but also to two other future kings: Ptolemy andCassander. Aristotle encouraged Alexander toward eastern conquest and his attitude towards Persia was unabashedly ethnocentric. In one famous example, he counsels Alexander to be "a leader to the Greeks and a despot to the barbarians, to look after the former as after friends and relatives, and to deal with the latter as with beasts or plants".

By 335 BC, Artistotle had returned to Athens, establishing his own school there known as theLyceum. Aristotle conducted courses at the school for the next twelve years. While in Athens, his wife Pythias died and Aristotle became involved with Herpyllis of Stagira, who bore him a son whom he named after his father, Nicomachus. According to the Suda, he also had an eromenos, Palaephatus of Abydus.

This period in Athens, between 335 and 323 BC, is when Aristotle is believed to have composed many of his works. He wrote many dialogues of which only fragments have survived. Those works that have survived are in treatise form and were not, for the most part, intended for widespread publication; they are generally thought to be lecture aids for his students. His most important treatises includePhysics, Metaphysics, Nicomachean Ethics, Politics, De Anima (On the Soul) and Poetics.

Aristotle not only studied almost every subject possible at the time, but made significant contributions to most of them. In physical science, Aristotle studied anatomy, astronomy, embryology, geography, geology, meteorology, physics and zoology. In philosophy, he wrote on aesthetics, ethics, government, metaphysics, politics, economics, psychology, rhetoric and theology. He also studied education, foreign customs, literature and poetry. His combined works constitute a virtual encyclopedia of Greek knowledge.

Near the end of his life, Alexander and Aristotle became estranged over Alexander's relationship with Persia and Persians. A widespread tradition in antiquity suspected Aristotle of playing a role in Alexander's death, but there is little evidence.

Following Alexander's death, anti-Macedonian sentiment in Athens was rekindled. In 322 BC, Eurymedon the Hierophant denounced Aristotle for not holding the gods in honor, prompting him to flee to his mother's family estate in Chalcis, explaining: "I will not allow the Athenians to sin twice against philosophy" – a reference to Athens's prior trial and execution of Socrates. He died in Euboea ofnatural causes later that same year, having named his student Antipater as his chief executor and leaving a will in which he asked to be buried next to his wife.