Every living thing is a sort of imperialist, seeking to transform as much as possible of its environment into itself.

We have, in fact, two kinds of morality side by side: one which we preach but do not practice, and another which we practice but seldom preach.

It is undesirable to believe a proposition when there is no ground whatsoever for supposing it is true.

The fact that an opinion has been widely held is no evidence whatever that it is not utterly absurd; indeed, in view of the silliness of the majority of mankind, a widespread belief is more likely to be foolish than sensible.

Men fear thought as they fear nothing else on earth -- more than ruin -- more even than death.... Thought is subversive and revolutionary, destructive and terrible, thought is merciless to privilege, established institutions, and comfortable habit. Thought looks into the pit of hell and is not afraid. Thought is great and swift and free, the light of the world, and the chief glory of man.

Too little liberty brings stagnation and too much brings chaos.

The main things which seem to me important on their own account, and not merely as means to other things, are knowledge, art, instinctive happiness, and relations of friendship or affection.

This is one of those views which are so absolutely absurd that only very learned men could possibly adopt them.

If there were in the world today any large number of people who desired their own happiness more than they desired the unhappiness of others, we could have paradise in a few years.

We know very little, and yet it is astonishing that we know so much, and still more astonishing that so little knowledge can give us so much power.