The idea of libido (while maintaining its sexual meaning in the author’s sense as long as possible) offers us the dynamic value which we are seeking in order to explain the shifting of the psychological scenery. With this conception it is much simpler to formulate the phenomena in question, instead of by the incomprehensible substitution of the homo- by the hetero-sexual component. We may say now that the libido has gradually withdrawn from its homo-sexual manifestation and is transferred in the same measure into a hetero-sexual manifestation. Thus the homo-sexual component practically disappears. It remains only an empty possibility, signifying nothing in itself. Its very existence, therefore, is rightly denied by the laity, just as we doubt the possibility that any man selected at random would turn out to be a murderer. By the use of this conception of libido many relations 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