This does not mean that there is another phase of sex unclassified, but rather it proves the union in one Whole Entity of the two distinct principles, and by this fact of the "twain made one" we may know that Sex is the very crux of the cosmic law; that not only does it survive the mere physical expression of the law, but that the object of the sex-function is the spiritual union of the two principles, a male and a female entity, forming one complete and perfect Being—the true representative of the bi-une Being whom we know as God.
— from Sex--The Unknown Quantity: The Spiritual Function of Sex by Alexander J. (Alexander James) McIvor-Tyndall