According to Plato, it was at his trial that Socrates made his famous remark that the unexamined life is not worth living. In context, Socrates is choosing death, which he prefers to the delusion and folly in which most people live. For Socrates, the point of being human is to practice philosophy, to question everything. If one does not take advantage of the opportunities afforded by having a reasoning, questioning brain, then one might as well be an animal or even a vegetable. For that matter, one might as well be dead. This is what Socrates means when he says that the unexamined life is not worth living.
There certainly seems to be a positive corollary which follows from Socrates's statement. It is possible that no life is worth living, but if Socrates thought that, he would probably have said so. The corollary, therefore, is that the examined life is worth living, that Socrates's life, which was a complete failure in vulgar worldly terms, was worth living. This is an inspiring message, since it makes the meaning of life dependent not on the world, or on God, but on you. If you use your ability to think and reason, to examine your life and decide what is good about it and what you want to do with it, then your life has meaning. Since the meaning lies in the examination itself then, paradoxically, even if you find no meaning in life or in your life, you have created some just by searching for it.