(_a_) As a result of long years of onanism, which finally causes
impotence for women with continuance of intense sexual desire.
(_b_) As a result of severe mental disease (senile dementia,
brain-softening of the insane, etc.), in which, as experience teaches,
an inversion of the sexual instinct may take place.
Passive pederasty occurs:—
I. As a _non-pathological_ phenomenon:—