We may insist as often as we like that man's intellect is powerless in comparison to his instinctual life, and we may be right in this. Nevertheless, there is something peculiar about this weakness. The voice of the intellect is a soft one, but it will not rest until it has gained a hearing. Finally, after a countless succession of rebuffs, it succeeds.
Sigmund FreudThe adoption of the required attitude of mind towards ideas that seem to emerge "of their own free will" and the abandonment of the critical function that is normally in operation against them seem to be hard of achievement for some people. The "involuntary thoughts" are liable to release a most violent resistance, which seeks to prevent their emergence. If we may trust that great poet and philosopher Friedrich Schiller, however, poetic creation must demand an exactly similar attitude.
Sigmund Freud