We know less about the sexual life of little girls than of boys. But we need not feel ashamed of this distinction; after all, the sexual life of adult women is a 'dark continent' for psychology.
Sigmund FreudOnly the real, rare, true scientific minds can endure doubt, which is attached to all our knowledge.
Sigmund FreudEven if all parts of a problem seem to fit together like the pieces of a jigsaw puzzle, one has to remember that the probable need not necessarily be the truth and the truth not always probable.
Sigmund Freud