The parallelism is perfect. All the acts and situations used by the sadist in the active _rôle_ become the object of the desire of the masochist in the passive _rôle_. In both perversions these acts advance from purely symbolic acts to severe maltreatment. Even murder, in which sadism reaches its acme, finds, as is shown by Case 54,—of course, only in fancy,—its passive counterpart. Under favoring conditions, both perversions may occur with a normal vita sexualis; in both, the acts in which they express themselves are preparatory for coitus or substitutes for it.[85] But the analogy does not exist simply in external manifestation; it also extends to the subjective character of both perversions. Both are to be regarded as original psychopathies in mentally abnormal individuals, who, in particular, are affected with psychical hyperæsthesia sexualis, and, as a rule, also with other abnormalities; and for each of these perversions two constituent elements may be demonstrated, which have their roots in psychical facts lying within physiological limits. For masochism, as shown above, these elements lie in the fact (1) that in the state of sexual emotion every impression produced by the consort, independently of the manner of its production, is, _per se_, attended with lustful pleasure, which, where there is hyperæsthesia sexualis, may go so far as to over-compensate all painful sensation; and in the fact (2) that “sexual bondage,” dependent on mental factors that are in themselves not perverse, may, under pathological conditions, become a perverse, pleasurable desire for subjection to the opposite sex, which—even if it be quite unnecessary to assume its inheritance from the female side—represents a pathological degeneration of the character belonging to woman,—of the instinct of subordination, physiological in woman. In harmony with this, there are, likewise, two constituent elements explanatory of sadism, the origin of which may also be traced back within physiological limits. These are: the fact (1) that in sexual emotion, to a certain extent, as an accompanying psychical excitation, an impulse may arise to influence the object of desire in every possible way and with the greatest possible intensity, which, in individuals sexually hyperæsthetic, may become an impulse to inflict pain; and the fact (2) that, under pathological conditions, the man’s active _rôle_ of winning woman may become an unlimited desire for subjugation. Thus masochism and sadism represent perfect counterparts. It is also in harmony with this that the individuals affected with these perversions regard the opposite perversion in the other sex as their ideal, as shown by Case 44 and Case 50, and also by “Rousseau’s Confessions.”