Tertullian

“ For the discussion of these questions we abandoned, if I remember rightly, ground to which we must now return. We had established the position that the soul is seminally placed in man, and by human agency, and that its seed from the very beginning is uniform, as is that of the soul also, to the race of man ”

“ The soul, being sown in the womb at the same time as the body, receives likewise along with it its sex; and this indeed so simultaneously, that neither of the two substances can be alone regarded as the cause of the sex. ”

“ Now, if in the semination of these substances any interval were admissible in their conception, in such wise that either the flesh or the soul should be the first to be conceived, one might then ascribe an especial sex to one of the substances, owing to the difference in the time of the impregnations, so that either the flesh would impress its sex upon the soul, or the soul upon the sex ”