The most complicated achievements of thought are possible without the assistance of consciousness.

As regards intellectual work it remains a fact, indeed, that great decisions in the realm of thought and momentous discoveries and solutions of problems are only possible to an individual, working in solitude.

In the last analysis the entire field of psychology may reduce to biological electrochemistry.

I cannot face with comfort the idea of life without work; work and the free play of the imagination are for me the same thing, I take no pleasure in anything else.

The Irish are the one race for which psychoanalysis is of no use whatsoever... because they already live in a dream world.

The primitive stages can always be re-established; the primitive mind is, in the fullest meaning of the word, imperishable.

Properly speaking, the unconscious is the real psychic; its inner nature is just as unknown to us as the reality of the external world, and it is just as imperfectly reported to us through the data of consciousness as is the external world through the indications of our sensory organs.