Read "Three Essays on the Theory of Sexuality" by Sigmund Freud online for free on Textopian. Full text with search, annotations, highlights, and AI-powered reading aids.
The extraordinary frequent discoveries of apparently abnormal and exceptional sexual manifestations in childhood, as well as the discovery of infantile reminiscences in neurotics, which were hitherto unconscious, allow us to sketch the following picture of the sexual behavior of childhood.
It seems certain that the newborn child brings with it the germs of sexual feelings which continue to develop for some time and then succumb to a progressive suppression, which is in turn broken through by the proper advances of the sexual development and which can be checked by individual idiosyncrasies. Nothing is known concerning the laws and periodicity of this oscillating course of development. It seems, however, that the sexual life of the child mostly manifests itself in the third or fourth year in some form accessible to observation.