(Second objection): Please explain how differing individuals are
born from the same parents. This diversity, if it be anything
more than merely apparent, depends on the manner in which the two
generating principles concur in the act of generation; at one time
the male predominates, at other times, the female; again, they may
both act equally. In either case, the ("seminal) reason" is given in
its entirety, and dominates the matter furnished by either of the
generating principles.