The advance of scientific knowledge does not seem to make either our universe or our inner life in it any less mysterious.

Man armed with science is like a baby with a box of matches.

Until politics are a branch of science, we shall do well to regard political and social reforms as experiments rather than short-cuts to the millennium.

There can be no truce between science and religion.

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

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.

Quantitative work shows clearly that natural selection is a reality, and that, among other things, it selects Mendelian genes, which are known to be distributed at random through wild populations, and to follow the laws of chance in their distribution to offspring. In other words, they are an agency producing variation of the kind which Darwin postulated as the raw material on which selection acts.