We here may consider the effects of infantile sexual investigation. Freud says its activity labours with the desire for looking, though it cannot be added to the elementary components of the impulses. Many readers may refuse to follow Freud here, where he concludes that the great desire for knowledge in later life may be traced to this infantile sexual curiosity. But that there must be some connection cannot be doubted. A child who has never displayed any curiosity as to where it came from must be one in whom the desire for knowledge has not been and probably never will be strongly developed. The child is the father of the student man. Freud asserts in his study of Leonardo da Vinci that there are three sublimations in later life of this curiosity, the most important and rarest being where a pure scientific investigation replaces the sexual activity and is not occupied with sexual themes. Thus he explains the scientific work of Leonardo and his chaste life. III Let us now take up the other two partial impulses, sadism and masochism, noted by Freud, and see their effect on the literary work of a man in later life. "The repression of the sadistic impulse," says Dr. Brink, "produces not its annihilation but merely its transfer from consciousness to unconsciousness. And there, withheld from the neutralising influence of conscious reasoning, the impulse and the phantasies derived from it are not only preserved without deterioration but may even grow in vigour and intensity. Thus, despite the fact that in many instances the individual's conscious life is apparently singularly irreproachable, nevertheless this life is lived coincidently with an undercurrent of impulses of anger, hate, hostility and revenge and their corresponding phantasies" (_Morbid Fears_, page 291). This would account for the tales of horror we find in Poe, Kipling and Jack London. To-day we do not always assault or kill our enemies. Literary men do so by depicting scenes in literature where this is done. Jack London describes fist fights in which he is always defeating his enemies. It is said that in real life he boasted of his abilities as a fighter. Pfister, in his _Psychoanalytic Method_, formulates a law from an earlier work of his, as follows: "The repressed hate of certain individuals forms phantasies out of suitable contents of experiences, either actual or imaginary, according to the laws of the dream-work, by which procedure it creates for itself imaginary gratification. This gratification of complex comes about through the mechanism of a disguised wish, directed towards the injury of the hated person, being represented in the content of the waking dream as realised."