that "there is no such thing
as a pure male or female animal, but that all contain a dominant
and recessive sex, except those hermaphrodites in which both
sexes are equally represented.... There seems to me ample
evidence for the conclusion that there is no such thing as a pure
male or female." F.H.A. Marshall, again, in his standard manual,
_The Physiology of Reproduction_ (1910, p. 655 et seq.), is
inclined to accept the same view. "If it be true," he remarks,
"that all individuals are potentially bisexual and that changed
circumstances, leading to a changed metabolism, may, in
exceptional circumstances, even in adult life, cause the
development of the recessive characters, it would seem extremely
probable that the dominance of one set of sexual characters over
the other may be determined in some cases at an early stage of
development in response to a stimulus which may be either
internal or external." So also Berry Hart ("Atypical Male and
Female Sex-Ensemble," a paper read before Edinburgh Obstetrical
Society, _British Medical Journal_, June 20, 1914, p. 1355)
regards the normal male or female as embodying a maximum of the
potent organs of his or her own sex with a minimum of non-potent
organs of the other sex, with secondary sex traits congruent. Any
increase in the minimum gives a diminished maximum and
non-congruence of the secondary characters.

We thus see that the ancient medico-philosophic conception of organic
bisexuality put forth by the Greeks as the key to the explanation of
sexual inversion, after sinking out of sight for two thousand years, was
revived early in the nineteenth century by two amateur philosophers who
were themselves inverted (Hoessli, Ulrichs), as well as by a genuine
philosopher who was not inverted (Schopenhauer). Then the conception of
latent bisexuality, independently of homosexuality, was developed from the
purely scientific side (by Darwin and evolutionists generally). In the
next stage this conception was adopted by the psychiatric and other
scientific authorities on homosexuality (Krafft-Ebing and the majority of
other students). Finally, embryologists, physiologists of sex and
biologists generally, not only accept the conception of bisexuality, but
admit that it probably helps to account for homosexuality. In this way the
idea may be said to have passed into current thought. We cannot assert