If it's not one thing, it's your mother.

I have an infamously low capacity for visualizing relationships, which made the study of geometry and all subjects derived from it impossible for me.

I take up the standpoint that the tendency to aggression is an innate, independent, instinctual disposition in man, and I come back now to the statement that it constitutes the most powerful obstacle to culture.

We must reckon with the possibility that something in the nature of the sexual instinct itself is unfavorable to the realization of complete satisfaction.

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.

Sadism is all right in its place, but it should be directed to proper ends.

A love that does not discriminate seems to me to forfeit a part of its own value, by doing an injustice to its object; and secondly, not all men are worthy of love.