A fairly bright boy is far more intelligent and far better company than the average adult.

You can drop a mouse down a thousand-yard mine shaft and, on arriving at the bottom, it gets a slight shock and walks away. A rat would probably be killed, though it can fall safely from the eleventh story of a building, a man is broken, a horse splashes.

To the biologist the problem of socialism appears largely as a problem of size.

Would I lay down my life to save my brother? No, but I would to save two brothers or eight cousins.

It seems to me immensely unlikely that mind is a mere by-product of matter. For if my mental processes are determined wholly by the motions of atoms in my brain I have no reason to suppose that my beliefs are true. They may be sound chemically, but that does not make them sound logically. And hence I have no reason for supposing my brain to be composed of atoms.

There is no great invention, from fire to flying, which has not been hailed as an insult to some god.

This is my prediction for the future: Whatever hasn't happened will happen, and no one will be safe from it.