It was the ghost of rationality itself ... This is the ghost of normal everyday assumptions which declares that the ultimate purpose of life, which is to keep alive, is impossible, but that this is the ultimate purpose of life anyway, so that great minds struggle to cure diseases so that people may live longer, but only madmen ask why. One lives longer in order that he may live longer. There is no other purpose. That is what the ghost says.

One of the most moral acts is to create a space in which life can move forward.

Definitions are the foundation of reason. You can't reason without them.

No one is fanatically shouting that the sun is going to rise tomorrow. They know it's going to rise tomorrow.

Sanity is not truth. Sanity is conformity to what is socially expected. Truth is sometimes in conformity, sometimes not.

One geometry cannot be more true than another; it can only be more convenient. Geometry is not true, it is advantageous.

One thing about pioneers that you don't hear mentioned is that they are invariably, by their nature, mess-makers. They go forging ahead, seeing only their noble, distant goal, and never notice any of the crud and debris they leave behind them.