Glossary: "Original Bisexuality"

The theory of original bisexuality arises in the nineteenth century out of the discovery in the nascent science of embryology that the human embryo is not sexed male or female at conception (in terms of the development of primary sexual organs, i.e., ovaries and testes) and that all human embryos contain the biological material to develop as either male or female. Scientists used the theory of the original dual-sexed, or bisexual, nature of the embryo as a launching point for a wide array of biological and psychiatric/psychoanalytic scientific inquiries, including research into hermaphroditism and inversion (homosexuality).