Sigmund Freud's theory on dreams

The interpretation of dreams is the royal road to a knowledge of the unconscious.
...dreams "are not meaningless, they are not absurd; they do not imply that one portion of our store of ideas is asleep while another portion is beginning to wake. On the contrary, they are psychical phenomena of complete validity.
...they are constructed by a highly complicated activity of the mind (op. cit., chapter "A Dream is the Fulfilment of a Wish".)
...a dream is a (disguised) fulfilment of a (suppressed or repressed) wish...(op. cit., chapter Distortion in Dreams.)
...it is the securest foundation of psychoanalysis and the field in which every worker must acquire his convictions and seek his training. If I am asked how one can become a psychoanalyst, I reply: By studying one's own dreams.(New Introductory Lectures on Psychoanalysis.)
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