An Athenian philosopher who wrote nothing but transformed Western philosophy — through the practice of public questioning he called elenchus, his conviction that the unexamined life is not worth living, and his trial and execution for impiety and corrupting the youth of Athens, which became the defining image of philosophy as a dangerous practice.
Socrates is the most influential philosopher in Western history who left no writings. Everything we know about him comes from others — primarily his student Plato, who may have used Socrates as a mask for his own ideas. The 'Socratic problem' — the question of what the historical Socrates actually believed — has never been fully resolved. What is certain is that his method of questioning, his insistence that wisdom begins with the acknowledgment of ignorance, and his willingness to die for his philosophical commitments transformed what philosophy was understood to be.