Our possibilities of happiness are already restricted by our constitution. Unhappiness is much less difficult to experience. We are threatened with suffering from three directions: from our own body, which is doomed to decay and dissolution and which cannot even do without pain and anxiety as warning signals; from the external world, which may rage against us with overwhelming and merciless forces of destruction; and finally from our relations to other men. The suffering which comes from this last source is perhaps more painful to us than any other.

My way of working was different years ago. I used to wait until an idea came to me. Now I go half-way to meet it, though I don't know whether I find it any the quicker.

Men are not gentle, friendly creatures wishing for love, who simply defend themselves if they are attacked, but ... a powerful measure of desire for aggression had to be reckoned as part of their instinctual endowment.

Humanity is in the highest degree irrational, so that there is no prospect of influencing it by reasonable arguments. Against prejudice one can do nothing.

Sexual morality - as society in its extreme form, the American, defines it - is contemptible. I advocate an incomparably freer sexual life.

The religions of mankind must be classed among the mass-delusions of this kind. No one, needless to say, who shares a delusion ever recognizes it as such.

Men are strong so long as they represent a strong idea they become powerless when they oppose it.