Religious illusion must bow to scientific truth. It is in total error about the nature of the true world. Only science is not an illusion.

What progress we are making. In the Middle Ages they would have burned me. Now they are content with burning my books.

The unconscious of one human being can react upon that of another without passing through the conscious.

If youth knew; if age could.

Neurosis is the result of a conflict between the ego and its id, whereas psychosis is the analogous outcome of a similar disturbance in the relation between the ego and the external world.

Man has, as it were, become a kind of prosthetic God.

The study of dreams may be considered the most trustworthy method of investigating deep mental processes. Now dreams occurring in traumatic neuroses have the characteristic of repeatedly bringing the patient back into the situation of his accident, a situation from which he wakes up in another fright.