The Interpretation of Dreams

They distinguished between true and valuable dreams, sent to the dreamer to warn him or to foretell the future, and vain, fraudulent, and empty dreams, the object of which was to misguide or lead him to destruction.

Accumulation of semen produces voluptuous dreams, and local pain the idea of suffering ill treatment, of hostile attacks, or of accidental bodily injuries.

Wherever the enumeration of dream sources is complete we ultimately find four forms, which are also utilised for the division of dreams:—
I. External (objective) sensory stimuli.
II. Internal (subjective) sensory stimuli.
III. Internal (organic) physical excitations.
IV. Purely psychical exciting sources.