Other people can talk about how to expand the destiny of mankind. I just want to talk about how to fix a motorcycle. I think that what I have to say has more lasting value.

Of course, the laws of science contain no matter and have no energy either and therefore do not exist except in people's minds. It's best to be completely scientific about the whole thing and refuse to believe in either ghosts or the laws of science. That way you're safe. That doesn't leave you very much to believe in, but that's scientific too.

That's all the motorcycle is, a system of concepts worked out in steel.

When you live in the shadow of insanity, the appearance of another mind that thinks and talks as yours does is something close to a blessed event.

In the high country of the mind one has to become adjusted to the thinner air of uncertainty.

We must understand that when a society undermines intellectual freedom for its own purposes it is absolutely morally bad, but when it represses biological freedom for its own purposes it is absolutely morally good.

Metaphysics is a restaurant where they give you a thirty thousand page menu, and no food.