For Socrates, as for Jesus Christ, we have few biographical details, and nearly all those we have come from his greatest admirer. But it is clear that Socrates contributed three new ideas to the development of philosophy: that goodness consists not in helping friends and harming enemies, but in not harming anybody at all; that goodness and knowledge are one and the same thing; and that for progress to be made in argument, there must be step-by-step agreement between those arguing. The similarity to Jesus goes further. Socrates too was put to death for defying the conventions of his day; and he too sets us, by the manner of his life and his death, an example which is at the same time an inspiration and an impossible ideal. Socrates was born in Athens in 469bce, and spent much of his life pointing out the absurdities of current beliefs. Though he played no part in political life, he antagonized both the democratic and oligarchic factions in Athens, and in 399bce was put to death on a charge of atheism and corrupting the young. By the manner of his life and death he became the inspiration for the philosopher Plato.