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.

In human beings pure masculinity or femininity is not to be found either in a psychological or biological sense.

Man has, as it were, become a kind of prosthetic God. When he puts on all his auxiliary organs, he is truly magnificent; but those organs have not grown on him and they still give him much trouble at times.

The whole thing [religion] is so patently infantile, so foreign to reality, that to anyone with a friendly attitude to humanity it is painful to think that the great majority of mortals will never be able to rise above this view of life.

The meager satisfaction that man can extract from reality leaves him starving.

The ego is not master in its own house.

Desire presses ever forward unsubdued.