Socrates - 469 - 399 BC Socrates (469 399 BC) was an ancient Greek philosopher who is widely credited with laying the foundation for Western philosophy. Perhaps his most important contribution to Western thought is dialectics (answering a question with a question) method of inquiry, known as the Socratic Method. He applied this to the examination of key moral concepts such as Good and Justice.

His reputation was such, that the Oracle of Delphi was asked if anyone was wiser than Socrates - to which the answer was no.
Socrates decided that that this was a riddle, and questioned other Athenians about their knowledge of good, beauty, and virtue. Socrates concluded that the truly wise man, is simply the man who knows how ignorant he is.

Socrates' public ridiculing of those in power led to a trial on corrupting the young. He was found guilty as charged, and sentenced to death by drinking a silver goblet of hemlock. Having agreed to live under Athen's laws, to have foregone this punishment would have been against his own philosophy, and he therefore complied with the sentence.