Robert A. Heinlein

It seems to me that any law that is not enforced and can’t be enforced weakens all other laws.

Self-pity, he said, is the most demoralizing of all vices.

It is hard to shake off any taboos a child is indoctrinated with in his earliest years. Even if he learns later that they are nonsense.

Natural laws have no pity.

Stupidity cannot be cured with money, or through education, or by legislation. Stupidity is not a sin, the victim can't help being stupid. But stupidity is the only universal capital crime; the sentence is death, there is no appeal, the execution is carried out automatically and without pity.

Men rarely (if ever) manage to dream up a god superior to themselves. Most gods have the manners and morals of a spoiled child.

Anything worth doing is worth overdoing.

A competent and self-confident person is incapable of jealousy in anything. Jealousy is invariably a symptom of neurotic insecurity.

If you are part of a society that votes, then do so. There may be no candidates and no measures you want to vote for, but there are certain to be ones you want to vote against. In case of doubt, vote against. By this rule you will rarely go wrong. If this is too blind for your taste, consult some well-meaning fool (there is always one around) and ask his advice. Then vote the other way. This enables you to be a good citizen (if such is your wish) without spending the enormous amount of time on it that truly intelligent exercise of franchise requires.

Taxes are not levied for the benefit of the taxed.

Beware of altruism. It is based on self-deception, the root of all evil.

Anyone who cannot cope with mathematics is not fully human. At best he is a tolerable subhuman who has learned to wear shoes, bathe, and not make messes in the house.