Just came across a short summary note in "the Catholic Encyclopedia," http://www.newadvent.org/cathen/14153a.htm
on the real source of HV's dogma, Stoicism:
The Stoics taught that all existence is material, and described the soul as a breath pervading the body. They also called it Divine, a particle of God (apospasma tou theu) — it was composed of the most refined and ethereal matter. Eight distinct parts of the soul were recognized by them:
the ruling reason (to hegemonikon)
the five senses;
the procreative powers.
Absolute immortality they denied; relative immortality, terminating with the universal conflagration and destruction of all things, some of them (e.g. Cleanthes and Chrysippus) admitted in the case of the wise man; others, such as Panaetius and Posidonius, denied even this, arguing that, as the soul began with the body, so it must end with it. Graeco-Roman philosophy made no further progress in the doctrine of the soul in the age immediately preceding the Christian era. None of the existing theories had found general acceptance, and in the literature of the period an eclectic spirit nearly akin to Scepticism predominated. Of the strife and fusion of systems at this time the works of Cicero are the best example. On the question of the soul he is by turns Platonic and Pythagorean, while he confesses that the Stoic and Epicurean systems have each an attraction for him. Such was the state of the question in the West at the dawn of Christianity.
The reference to Cicero is interesting, as the CCC cites him as its authority on the existence of natural law, the basis of HV.
In Jewish circles a like uncertainty prevailed. The Sadducees were Materialists, denying immortality and all spiritual existence. The Pharisees maintained these doctrines, adding belief in pre-existence and transmigration. The psychology of the Rabbins is founded on the Sacred Books, particularly the account of the creation of man in Genesis. Three terms are used for the soul: nephesh, nuah, and neshamah; the first was taken to refer to the animal and vegetative nature, the second to the ethical principle, the third to the purely spiritual intelligence. At all events, it is evident that the Old Testament throughout either asserts or implies the distinct reality of the soul. An important contribution to later Jewish thought was the infusion of Platonism into it by Philo of Alexandria. He taught the immediately Divine origin of the soul, its pre-existence and transmigration; he contrasts the pneuma, or spiritual essence, with the soul proper, the source of vital phenomena, whose seat is the blood; finally he revived the old Platonic Dualism, attributing the origin of sin and evil to the union of spirit with matter.
It was Christianity that, after many centuries of struggle, applied the final criticisms to the various psychologies of antiquity, and brought their scattered elements of truth to full focus. The tendency of Christ's teaching was to centre all interest in the spiritual side of man's nature; the salvation or loss of the soul is the great issue of existence. The Gospel language is popular, not technical. Psyche and pneuma are used indifferently either for the principle of natural life or for spirit in the strict sense. Body and soul are recognized as a dualism and their values contrasted: "Fear ye not them that kill the body . . . but rather fear him that can destroy both soul and body in hell."
In St. Paul we find a more technical phraseology employed with great consistency. Psyche is now appropriated to the purely natural life; pneuma to the life of supernatural religion, the principle of which is the Holy Spirit, dwelling and operating in the heart. The opposition of flesh and spirit is accentuated afresh (Romans 1:18, etc.). This Pauline system, presented to a world already prepossessed in favour of a quasi-Platonic Dualism, occasioned one of the earliest widespread forms of error among Christian writers — the doctrine of the Trichotomy. According to this, man, perfect man (teleios) consists of three parts: body, soul, spirit (soma, psyche, pneuma). Body and soul come by natural generation; spirit is given to the regenerate Christian alone. Thus, the "newness of life", of which St. Paul speaks, was conceived by some as a superadded entity, a kind of oversoul sublimating the "natural man" into a higher species.
It is odd that "the magisterium
Nihil Obstat. July 1, 1912. Remy Lafort, S.T.D., Censor. Imprimatur. +John Cardinal Farley, Archbishop of New York
condemns Trichotomy as "error," in favor of creationism
Tertullian's treatise "De Anima" has been called the first Christian classic on psychology proper. The author aims to show the failure of all philosophies to elucidate the nature of the soul, and argues eloquently that Christ alone can teach mankind the truth on such subjects. His own doctrine, however, is simply the refined Materialism of the Stoics, supported by arguments from medicine and physiology and by ingenious interpretations of Scripture, in which the unavoidable materialism of language is made to establish a metaphysical Materialism. Tertullian is the founder of the theory of Traducianism, which derives the rational soul ex traduce, i.e. by procreation from the soul of the parent. For Tertullian this was a necessary consequence of Materialism. Later writers found in the doctrine a convenient explanation of the transmission of original sin. St. Jerome says that in his day it was the common theory in the West. Theologians have long abandoned it, however, in favour of Creationism, as it seems to compromise the spirituality of the soul...St. Thomas's doctrine is briefly as follows...the rational soul is produced by special creation at the moment when the organism is sufficiently developed to receive it. In the first stage of embryonic development, the vital principle has merely vegetative powers; then a sensitive soul comes into being, educed from the evolving potencies of the organism — later yet, this is replaced by the perfect rational soul, which is essentially immaterial and so postulates a special creative act. Many modern theologians have abandoned this last point of St. Thomas's teaching, and maintain that a fully rational soul is infused into the embryo at the first moment of its existence.
for if semen has no connection to the soul or spirit, it's odd that the Vatican, arguing for it being merely only genetic material puts such spiritual importance on its demise (which can't be helped, even in normal conception): it upholds the conclusions of the Stoics while refusing to admit their basis for those conclusions.
The Stoics ranking of procreation as a constituent part of the individual soul and the connection with the Stoic god (although they were queasy about baldly equating sperm with the universal logos) merged with the common idea of semen being the essence of a man (and why women were just incubaters), the idea being that blood from every part of the body congealed in semen. Of course, a sperm cannot be the essence of a human person: a human person has 46 chromosomes, and a sperm only has 23. That is what St. Clement of Alexandria adopted (without grounding it in Christianity), along with the Stoics abhorrence of shaving (another aspect of their materialism).