By profession a biologist, [Thomas Henry Huxley] covered in fact the whole field of the exact sciences, and then bulged through its four fences. Absolutely nothing was uninteresting to him. His curiosity ranged from music to theology and from philosophy to history. He didn't simply know something about everything; he knew a great deal about everything.

The ideal state for a philosopher, indeed, is celibacy tempered by polygamy.

I believe that any man who takes the liberty of another into his keeping is bound to become a tyrant, and that any man who yields up his liberty, in however slight the measure, is bound to become a slave.

The average man never really thinks from end to end of his life. The mental activity of such people is only a mouthing of cliches. What they mistake for thought is simply a repetition of what they have heard. My guess is that well over 80 percent of the human race goes through life without having a single original thought.

The law is a sort of hocus-pocus science that smiles in your face while it picks your pocket.

Men become civilized, not in proportion to their willingness to believe, but in their readiness to doubt.

For the habitual truth-teller and truth-seeker, indeed, the whole world has very little liking. He is always unpopular.