Psychoanalysis is in essence a cure through love.

The whole life of instinct serves the one end of bringing about death.

Only the real, rare, true scientific minds can endure doubt, which is attached to all our knowledge.

A state of consciousness is characteristically very transitory; an idea that is conscious now is no longer so a moment later, although it can become so again under certain conditions that are easily brought about.

The wish to be able to fly is to be understood as nothing else than a longing to be capable of sexual performance.

There is an intellectual function in us which demands unity, connection and intelligibility from any material, whether of perception or thought, that comes within its grasp; and if, as a result of special circumstances, it is unable to establish a true connection, it does not hesitate to fabricate a false one.

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.