There is no likelihood of our being able to suppress humanity's aggressive tendencies... Complete suppression of man's aggressive tendencies is not an issue; what we may try is to direct it into a channel other than that of warfare.

The time comes when each of us has to give up as illusions the expectations which, in his youth, he pinned upon his fellow-men, and when he may learn how much difficulty and pain has been added to his life by their ill-will.

I was making frequent use of cocaine at that time ... I had been the first to recommend the use of cocaine, in 1885, and this recommendation had brought serious reproaches down on me.

The paranoid is never entirely mistaken.

The madman is a dreamer awake

No neurotic harbors thoughts of suicide which are not murderous impulses against others redirected upon himself.

The great question that has never been answered, and which I have not yet been able to answer, despite my thirty years of research into the feminine soul, is 'What does a woman want?'