For Socrates, the main focus of his philosophical life was to tear down the pretensions of the so called "wise men" of Athens. He famously said "all that I know is that I know nothing", meaning that unlike the others, he was at least wise enough to realize the extent of his ignorance. For him, teaching philosophy was as much about unlearning what you thought you knew, as it was teaching the truth about the world. Of course, in practice, when you learn a bit of philosophy the exact opposite occurs, and after a couple classes you think you understand all of the deepest mysteries of the universe. What can you do though?