Freud makes a number of significant and surprisingly progressive points in this work. Building on and responding to the work of sexologists such as Krafft-Ebing and Ulrich. In the first essay, “The Sexual Aberrations,” Freud addresses inversion, fetishes, and other “aberrations.” Significantly, he observes that sexual inversion varies: while some are only attracted to those of the same sex, others can be attracted to both sexes, and even others engaged in sexual activity with those of the same sex under specific circumstances (location 123). Some have always had feelings for the same sex, while some can point to specific incidents which acted as a catalyst for these feelings (location 160). Further, many “inverts” are attracted to very feminine men, for example, which complicates the general understanding of inversion as a woman’s mind trapped in a man’s body. Importantly, he claims that, “The sexual impulse is probably entirely independent of its object and is not originated by the stimuli proceeding from the object” (location 236).
In his discussion of sadomasochism, Freud observes that “The sexuality of most men shows a taint of aggression, it is a propensity to subdue, the biological significance of which lies in the necessity of overcoming the resistance of the sexual object by actions other than mere courting” (location 349). When combined with his earlier characterization of the “conventional reticence and dishonesty of women” (273), the dynamics of heterosexuality as Freud observes them are troubling. However, it is also significant that Freud identifies that all “normal” sexual behavior contains elements of perversion, and “this universality suffices in itself to prove the inexpediency to prove the opprobrious application of the name perversion” (location 386). Further, it is also significant that Freud wishes to “find out how much of the biology of the sexual life of man can be discovered by means of psychological investigation” (location 114), instead of trying to find coincidences of sexual characteristics with physical markers, as so many before him tried to do. He also seems to be arguing for situational sexuality, as he says that there are very few people who truly prefer children or animals sexually to adults, but that most who prey upon the young or engage in bestiality do so out of cowardliness or lack of other partners (especially in the case of animals). Freud also argues for the existence of sexual urges from birth—not from puberty—and thus claims that sexual perversions can have their roots in childhood development and experience.