To stay young requires unceasing cultivation of the ability to unlearn old falsehoods.

At least once every human should have to run for his life, to teach him that milk does not come from supermarkets, that safety does not come from policemen, that 'news' is not something that happens to other people. He might learn how his ancestors lived and that he himself is no different--in the crunch his life depends on his agility, alertness, and personal resourcefulness.

Cheops' Law: Nothing ever gets built on schedule or within budget.

There are two ways of forming an opinion. One is the scientific method; the other, the scholastic. To the scientific mind, experimental proof is all-important, and theory is merely a convenience in description, to be junked when it no longer fits. To the academic mind, authority is everything, and facts are junked when they do not fit theory.

Some things, the more you understand the more you loathe them.

There is no conclusive evidence of life after death, but there is no evidence of any sort against it. Soon enough you will know, so why fret about it?

Physicians had gone to their graves calling Pasteur a liar, a fool, or worse—without examining evidence which their “common sense” told them was impossible.