- tions between the isolated sexual functions are now easily
explicable.
The early idea of the multiplicity of sexual components must be given up: it savors too much of the ancient philosophical notion of the faculties of the mind. Its place is taken by libido which is capable of manifold applications. The earlier components only represent possibilities of activities. With this conception of libido, the original idea of a divided sexuality with different roots is replaced by a dynamic unity, without which the formerly important components remain but empty possibilities of activities. This development in our conception is of great importance. We have here the same process which Robert Mayer introduced into dynamics. Just as the conception of the conservation of energy removed their character as elements from the forces, imparting to them the character of a manifestation of energy, so the libido theory similarly removes from the sexual components the idea of the mental "faculties" as elements ("Seelen Vermögen"), and ascribes to them merely phenomenal value. This conception represents the impression of reality far more than the theory of components. With a libido-theory we can easily explain the case of the young man. The disappointment he met with, just at the time he had definitely decided on a hetero-sexual life, drove his libido again from the hetero-sexual manifestation into a homo-sexual form, thus calling forth his entire homo-sexuality.
The Energic Theory of Libido
I must point out here that the analogy with the law of the conservation of energy is very close. In both cases the question arises when an effect of energy disappears, where is this energy meanwhile, and where will it reemerge? Applying this point of view as a heuristic principle to the psychology of human conduct, we shall make some astonishing discoveries. Then we shall see how the most heterogeneous phases of individual psychological development are connected in an energic relationship. Every time we see a person who is splenetic or has a morbid conviction, or some exaggerated mental attitude, we know here is too much libido, and the excess must have been taken away from some-
