may be designated as the dispositional and the definitive
groups. Constitution and occasional infantile experiences are just as
cooeperative in the first as disposition and later traumatic experiences
in the second group. All the factors which injure the sexual development
show their effect in that they produce a _regression_, or a return to a
former phase of development.

We may now continue with our task of enumerating the factors which have
become known to us as influential for the sexual development, whether
they be active forces or merely manifestations of the same.

*Prematurity.*--Such a factor is the spontaneous sexual _prematurity_
which can be definitely demonstrated at least in the etiology of the
neuroses, though in itself it is as little adequate for causation as the
other factors. It manifests itself in a breaking through, shortening, or
suspending of the infantile latency period and becomes a cause of
disturbances inasmuch as it provokes sexual manifestations which, either
on account of the unready state of the sexual inhibitions or because of
the undeveloped state of the genital system, can only carry along the
character of perversions. These tendencies to perversion may either
remain as such, or after the repression sets in they may become motive
powers for neurotic symptoms; at all events, the sexual prematurity
renders difficult the desirable later control of the sexual impulse by
the higher psychic influences, and enhances the compulsive-like
character which even without this prematurity would be claimed by the
psychic representatives of the impulse. Sexual prematurity often runs
parallel with premature intellectual development; it is found as such in
the infantile history of the most distinguished and most productive
individuals, and in such connection it does not seem to act as
pathogenically as when appearing isolated.

*Temporal Factors.*--Just like prematurity, other factors, which under
the designation of _temporal_ can be added to prematurity, also demand
consideration. It seems to be phylogenetically established in what
sequence the individual impulsive feelings become active, and how long
they can manifest themselves before they succumb to the influence of a
newly appearing active impulse or to a typical repression. But both in
this temporal succession as well as in the duration of the same,
variations seem to occur, which must exercise a definite influence on
the experience. It cannot be