Socrates, the best known of the ancient Greek philosophers, is renowned for his skill in argumentation and moral integrity. The English poet, Percy Shelley, referred to him as “the Jesus Christ of Greece”.

Socrates was born in 5th-century BC Athens, during the Golden Age of Pericles, when the acropolis was constructed and when the cultural life of the city was thriving.

He did not leave any writings behind, and so our knowledge of him depends entirely on the works of others, particularly the dialogues of his famous student Plato.

From these sources we know that he was married (to Xanthippe), had three sons, and served in the Athenian army in several battles with distinction.

We also know that he was very ugly but also very charismatic. Rather than taking up a job to earn a living he would roam the marketplace barefoot and unwashed, engaging in conversation and debates with a variety of people from slaves and craftsmen to prominent political and intellectual figures.

In these conversations, Socrates would seek answers to questions such as “What is courage?” and “What is knowledge?”

His interlocutors would provide what they assumed was a reasonable response, but Socrates would quickly show through a series of searching questions that their answers could not be correct.

Socrates therefore exposed these people, who often held positions of authority and power, as ignorant, and this made him a controversial and subversive figure. But Socrates was willing to accept that he too was ignorant.

The difference, however, was that Socrates was aware of his ignorance, whereas the others failed to recognise their ignorance.

And so when the Oracle of Delphi declared that Socrates the wisest of men, Socrates interpreted this to mean that he alone knew that he did not know anything.

According to Socrates, therefore, wisdom entails the recognition of one’s own ignorance.

He also taught that the unexamined life is not worth living, that a good person cannot be harmed by anything, and that no-one knowingly and freely does wrong.

At 70 years of age, Socrates was accused of corrupting the young and failing to acknowledge the gods of Athens. At his trial, which was over in a day, the jury found him guilty and condemned him to death.

His friends tried to persuade him to escape from prison, but he declined. Instead, he drank the poison hemlock, meeting his death fearlessly and nobly, as Plato was to say (Phaedo 58e).

Dr Nick Trakakis teaches Philosophy and Religious Studies at Monash and Deakin Universities. His most recent book is The End of Philosophy of Religion, published by Continuum in London.