After Plato's death (348/7 BC), Aristotle was the natural contender for the scholar of the Academy - but the other members of the Academy decided to choose Speusippus, Plato's nephew, because of the great divergence between the philosophical system developed by Aristotle and that of Plato. ¹⁾

Anaximander of Miletus (c. 610-546 BC) was one of the earliest Ionian natural philosophers, probably a student of Thales. He is suspected to have been the author of the first philosophical work in human history, known as Περὶ φύσεως (On Nature). He was the creator of the first map of the world and the author of the thesis that the stars revolve around the Pole Star. He was also the first philosopher to suggest that the Earth's surface is curved and that it can “float” in space. ²⁾

Protagoras with his views caused much controversy in Athens. He preached with his most important recorded sentence cognitive relativism. For his atheism, he was probably sentenced to be expelled from the Athenian community. ³⁾

In the Tusculan Disputations, Cicero discussed the issue of human happiness. This work was a praise of the power of human reason, which can control passions, pain, or fear of death. For centuries it was one of the most famous and quoted works of Cicero. Recommended in European schools and universities, they became one of the basic sources of European ethics through their universal character both theistic and atheistic. ⁴⁾

Gorgias of Leontinoi (480- 385 BC) - Greek philosopher, one of the ten most prominent speakers in Ancient Greece, a precursor of art theory, one of the leading sophists. He is the protagonist of Plato's dialogue “Gorgias”. The famous paradoxes of Gorgias are: Nothing exists. Even if there were something, it would be unknowable. Even if it were cognizable, it would still be impossible to convey knowledge about it. ⁵⁾