Simple question about souls

This is a very straightforward question, but I find it very hard to get a straight answer on this. I am asking without any underlying agenda.
I would greatly appreciate a straightforward answer to this straightforward question. When I have asked it in other contexts, the response is usually nothing but theological dodging and avoiding the question.
Very simply put:

When a human being is conceived, is the soul that is ‘attached’ to the zygote created ex nihilo at that time and ‘connected’ in some manner? Or are there a number of souls already ‘available’, one being selected, and joined with the zygote through some spiritual process.

I honesty do not know the Catholic theological position on this, and have struggled to find the answer.
The theological implications are massive regardless of what the answer is - but there is no point discussing them until we know exactly what Catholic teaching on the subject is.

Struggle no more… This isn’t everything - and it should serve as a start… Part 1 of 2

**[359] "In reality it is only in the mystery of the Word made flesh that the mystery of man truly becomes clear."224

St. Paul tells us that the human race takes its origin from two men: Adam and Christ. . . The first man, Adam, he says, became a living soul, the last Adam a life-giving spirit. The first Adam was made by the last Adam, from whom he also received his soul, to give him life. . . The second Adam stamped his image on the first Adam when he created him. That is why he took on himself the role and the name of the first Adam, in order that he might not lose what he had made in his own image. The first Adam, the last Adam: the first had a beginning, the last knows no end. The last Adam is indeed the first; as he himself says: "I am the first and the last."225

**[360] Because of its common origin the human race forms a unity , for “from one ancestor [God] made all nations to inhabit the whole earth”:226

O wondrous vision, which makes us contemplate the human race in the unity of its origin in God. . . in the unity of its nature, composed equally in all men of a material body and a spiritual soul; in the unity of its immediate end and its mission in the world; in the unity of its dwelling, the earth, whose benefits all men, by right of nature, may use to sustain and develop life; in the unity of its supernatural end: God himself, to whom all ought to tend; in the unity of the means for attaining this end;. . . in the unity of the redemption wrought by Christ for all.227

**[361] “This law of human solidarity and charity”,228 without excluding the rich variety of persons, cultures and peoples, assures us that all men are truly brethren.

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CCC 365 The unity of soul and body is so profound that one has to consider the soul to be the “form” of the body: i.e., it is because of its spiritual soul that the body made of matter becomes a living, human body; spirit and matter, in man, are not two natures united, but rather their union forms a single nature.

366 The Church teaches that every spiritual soul is created immediately by God - it is not “produced” by the parents - and also that it is immortal: it does not perish when it separates from the body at death, and it will be reunited with the body at the final Resurrection.


Part 2 of 2


**[362] The human person, created in the image of God, is a being at once corporeal and spiritual. The biblical account expresses this reality in symbolic language when it affirms that "then the LORD God formed man of dust from the ground, and breathed into his nostrils the breath of life; and man became a living being."229 Man, whole and entire, is therefore willed by God.

**[363] In Sacred Scripture the term “soul” often refers to human life or the entire human person .230 But “soul” also refers to the innermost aspect of man, that which is of greatest value in him,231 that by which he is most especially in God’s image: “soul” signifies the spiritual principle in man.

**[364] The human body shares in the dignity of “the image of God”: it is a human body precisely because it is animated by a spiritual soul, and it is the whole human person that is intended to become, in the body of Christ, a temple of the Spirit:232

Man, though made of body and soul, is a unity. Through his very bodily condition he sums up in himself the elements of the material world. Through him they are thus brought to their highest perfection and can raise their voice in praise freely given to the Creator. For this reason man may not despise his bodily life. Rather he is obliged to regard his body as good and to hold it in honor since God has created it and will raise it up on the last day. 233

365 The unity of soul and body is so profound that one has to consider the soul to be the “form” of the body:234 i.e., it is because of its spiritual soul that the body made of matter becomes a living, human body; spirit and matter, in man, are not two natures united, but rather their union forms a single nature.

**[366] The Church teaches that every spiritual soul is created immediately by God - it is not “produced” by the parents - and also that it is immortal: it does not perish when it separates from the body at death, and it will be reunited with the body at the final Resurrection.235

**[367] Sometimes the soul is distinguished from the spirit: St. Paul for instance prays that God may sanctify his people “wholly”, with “spirit and soul and body” kept sound and blameless at the Lord’s coming.236 The Church teaches that this distinction does not introduce a duality into the soul.237 “Spirit” signifies that from creation man is ordered to a supernatural end and that his soul can gratuitously be raised beyond all it deserves to communion with God.238

**[368] The spiritual tradition of the Church also emphasizes the heart , in the biblical sense of the depths of one’s being, where the person decides for or against God.239


It is not “attached” to the fertilized egg. The act of fertilization creates a new human person and as part of that creation, the act of creation involves including a soul AS PART OF THE NEW HUMAN PERSON.

Let me repeat that: when a human sperm and a human egg unite to form a new human person, G_D creates a new soul, individual and unique, and includes it as an unseen-but-essential element of that person’s creation.


The soul is what gives life to a living creature. It is not a separate material thing.

If a zygote is alive, it is by having a soul. If it is not alive, it is not a zygote. The soul is not attached or connected to the zygote, it is the zygote and without a soul it would not be a zygote.

When we say the soul is created immediately by God, we mean it does not come from somewhere else. It is not sitting on a shelf waiting to be handed out. Rather it is a transformation of material substance into a living being, not by adding more but by “forming” the material into living being.

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The soul is created immediately by God. Saying that the soul is “attached” to a fertilized egg paints a very Cartesian (substance dualism) picture of things, though.

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I believe and think it good Catholic understanding that the soul is the breath of God. God breaths a soul into the union of egg and sperm at the moment of conception.

The only relevant passage appears to be here:

So then the soul is created instantly at the point of impregnation by God?
It is immortal henceforth but did not always exist, and is created immediately at conception.

I think the theological implications are massive. I could start a hundred threads based on that simple answer, and again - I didn’t want to ask anything based on a simple assumption.
However, I think the most obvious question is that IF a soul is created immediately, and is effectively only as ‘old’ as the human being it is one with, what awareness and knowledge does such a soul have? When a baby dies, or even when a zygote fails to attach to the uterine wall and ‘dies’, what level of ‘enrichment’ has such a soul obtained? Certainly none, right?
There are many, many more questions.

I would note that the viewpoint of a soul and zygote being one and the same contradicts several early Church teachers such as Aquinas.

Can you rationalize the above with evolution and other living things such as animals?
Are you saying that human beings were not ‘alive’ until God decided that one specific homo sapiens reached an evolutionary plateau and then changed the process of impregnation to include a soul - at which point later in that person’s life the first sin was committed?

If the soul is created directly by God, then is He not deliberately creating a defective soul based on Original Sin? So the soul is created by God but inherits Original Sin because the parents are the vehicle God is using to initiate this living being with a soul?

I’m not trying to be difficult here. I’ve read about this at some depth from a theological perspective and there just seems like the problem of “Animation”, as it is called, doesn’t seem to have a satisfying answer no matter how it is addressed.

It depends perhaps on how you believe humans attain knowledge. From a Thomist perspective, a fetus in the womb can still begin to develop basic experiences that begin to impress very basic concepts, since a fetus has senses. A blastocyte, though? All that individuates it from others would be that it was instantiated by such and such matter at such and such time. At death by purely natural means (assuming God took no further action to provide it with infused knowledge) it would still, intellectually speaking, I think, be a blank slate.

The knowledge of the ECFs and St. Thomas on reproduction and gestation was much poorer than today. They had no knowledge of a zygote as we know it today or that a single sperm merged with an egg to form a unique organism. Following St. Thomas, if we do that, we can take his views on hylemorphism as general principles and apply it to what current knowledge we have of gestation

yes, I can see this - but the soul IS separated from the body at death, correct? So there is a component of substance dualism at some level, right?

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St. Thomas said that all living things had souls. Other souls of other animals provide purely material operations, their immanent causality allowed for nutritive and sensitive powers. Humans are different insofar as their soul also provides immaterial operation in terms of intellect while also allowing for material operations. So for other animals, based on its operations, it is a material principle while for humans it is firstly an immaterial principle which also does other things.

It would be a mistake however to think of a hylemorphic form as a life principle or separate substance. Every material thing has a substantial form, and that substantial form is what determines its nature and operations. St. Thomas simply calls forms with nutritive, sensitive, or rational operations “souls.” It’s not that the material thing has some form and then has a soul on top of that which makes it alive. It’s that its formal cause or form has certain immanent powers of causality such that we refer to it as a soul.

I’m going backwards here, but under a hylemorphic conception every material thing is under some substantial form. You cannot have matter without form. So a human person is not a human body plus a soul (certain phrasing which may sound like it is otherwise is specific to rejecting Platonist/Cartesian views of a person that a person is just the immaterial and the body just a vehicle), it is prime matter with the substantial form of a human being (or soul) that makes a human being. And that hydrogen molecule is prime matter given form by the substantial form of hydrogen. And that bar of gold is prime matter with the substantial form of gold.

That’s not the best explanation I could give.

This is very misleading. If you want to somehow say Aquinas said all living things had souls, you really need to change the definition of ‘soul’ because he also said animals have no intrinsic moral value whatsoever.

Every living being has a soul. Only humans have rational/immortal souls. Animals have animal souls, vegetables have vegetative souls. Animal in fact comes from anima, the Latin word for soul. To be an animal, one must have an anima.

A rational soul ”knows” it is loved by God from the first moment of its existence. That love is eternal, not learned by sensing but part of rationality itself. That makes the rational soul immortal.

It is difficult to explain things in two philosophical systems without getting confused. It is sometimes hard to explain things in one philosophical system!

Aquinas describes the soul as the form of the body. Think of Michelangelo’s David. It is a block of marble shaped to look like David. When did it become a statue of David? When it was a block of marble? When the image of David was imagined? Or when image and marble were merged into a single statue? the soul is much more than a shape, but it is a form for our body sort of like the image of David is the shape for the statue.

There is some debate among Thomists about whether the intellectual principle (soul) after death is a substance at all if it’s not “informing” any matter. Those who say it continues to be a substance might give a bit of a macabre example of a dog without a tail. Cut the tail off and you still have a dog. What was the tail is not a dog anymore. Cut off some legs and you still have a dog, even if the legs are no longer under the form of a dog. Cut off everything but the head which you keep alive by machinery and you still have a dog in the living head but not in the rest. There’s no dualism, there. The form continues to inform the remaining living parts that allow it to continue at least some of the operations it has the powers of. The tail and legs and bodies were not under separate substances prior to being separated, the dog’s form “informed” the whole thing as one substance. As for humans, the intellectual principle, being of immaterial operations, doesn’t decompose when the body does. But it’s not that it was a separate substance than the body, it’s just all that’s left that continues (in some manner) its operations. Albeit in an extremely handicapped manner with no ability to take in new info through the senses. That’s the “survivalist” position that some Thomist’s take. Corruptionists, like I said before, are those who reject that anything that could be called a substance continues at all even if the intellectual principle doesn’t degrade.

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Did you read the rest of the post? I can’t tell.

I’d be wary of this analogy. The block is always under the substantial form of marble, before and after. That it is then shaped like David is accidental to it being a substance of marble. We would call this accident an accidental form, and the statue a sort of artifact rather than a substance (though it is made of one or more substances), or even a natural “heap” or “pile.”

But how does this jive with evolution? The FIRST rational soul knew at the moment it was created that it was loved by God? All other souls prior to this leap did not? Why did God decide at some particular point in human history to create a rational soul as opposed to non-rational souls (which, of course, were the parents of that special person). According to your theory, Adam’s parents were animals? This actually makes sense from an evolutionary standpoint. But are you OK with it? It is very unsatisfying to me that God would operate that way. The original version of Christianity where God created man out of dust initially with a rational soul (literal interpretation of genesis) is a far more logically approach.

It just seems as if we are performing some radical theological and philosophical gymnastics to rationalize the real world (as presented by science/evolution.physics) with historical Christian theology.

Just a quick clarification, the Catholic position is not necessarily explained by a Cartesian substance dualism. I don’t believe, as far as dogma goes, it requires hylemorphism. I for one think that’s the best philosophical explanation for the dogma, but there’s a difference between the dogma itself and an explanation of it in either philosophical or scientific terms.

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