That fact that Athens could condemn its noblest citizen to death did more than make a profound impression on him. It was to shape the course of his entire philosophic endeavor.

Many of the Nazis were convicted after the war, but they were not convicted for being 'unreasonable'. They were convicted for being gruesome murderers.

What Plato was really asking was perhaps why a horse was a horse, and not, for example, a cross between a horse and a pig.

It is by no means certain that we advance our philosophical quest by reading Plato or Aristotle. It may increase our knowledge of history but not of the world.

If there is a god, he is not only a wizard at leaving clues behind. More than anything, he's a master of concealment. And the world is not something that gives itself away. The heavens still keep their secrets. There is little gossip amongst the stars. But no one has forgotten the Big Bang yet. Since then, silence has reigned supreme, and every thing there is moving away. One can still come across a moon. Or a comet. Just don't expect friendly greetings. No visiting cards are printed in space.

Since the Renaissance, people have had to get used to living their life on a random planet in the vast galaxy.

If we don't know where we are going, it can be helpful to know where we come from.