A few cells in a Petri-dish

Some apologists assert that a growing entity which has human “DNA” is a human being. Which would mean that a few human stem-cells in a Petri dish already counts as a human being. Even if they are grown to be a replacement for a failing organ. Or even if they are grown to be a twin of an already existing child.

Apart from the obvious problems, there is a fundamental question: “What is a human DNA”? A certain sequence of molecules? But there is no precise sequence of molecules which could be classified as a “human” DNA. There can be mutations, some minor, some major. At what point will the mutated DNA become a non-human DNA?

Biology comes to the “rescue”. In biology the definition of a species is that members of the species are able to interbreed with each other, and produce something that is also able to procreate. That is why the “mule” - the result of the cross-breeding of a horse and a donkey is neither a horse, nor a donkey.

So, if a mutant is biologically unable to procreate with another human, then it is not a new member of the human species. However, it can happen that two new members are compatible with each other, but not with some randomly selected “human”. Therefore we have some members of a brand new species - some entities that are NOT humans. How should we treat them? As “honorary” human beings? Sounds like a sensible idea… but then we treat others as if they were human beings, and yet, they are not.

So the biological definition of “human” is not sufficient. We need the philosophical approach, which is also endorsed by the church: “humans are rational animals”. But this is also problematic. A few cells in a Petri dish are definitely not rational animals. They are a collection of some cells - which MAY grow into someone we call a human being. Let’s place then into the uterus of a woman. Do they become a human being just because they are placed into a uterus? So a few growing cells (blastocyst) is not a human being - it could be called a “potential” human being - but ONLY as long as the DNA enables the result to procreate with an actual human being. Otherwise it could be a member of a brand new species.

And why should the “animal” part be considered essential? If there is a being, which is not composed of animal cells, but is able to think and act rationally, would that being become an “honorary” human?

Any opinions?

Somewhere in all this speculation would be a human soul which only God can give to human matter. The Church teaches this is at conception. The real question would be would these creatures have immortal souls?


Tissue biopsies and cultures aren’t human beings, any more than an amputated body part is a person.

The problem with embryonic stem cells is that the process of extracting the cells kills the embryo.

As opposed to stem cells from the umbilical chord, which kills no one.


When a spermatozoa penetrates an ovum, that’s conception, and God infuses a rational soul at that moment. “A person is a person no matter how small.”

God preserved Our Lady free from original sin at that first moment of Her life. And if you read the mystics like Ven. Mary of Agreda or Blessed Anne Catherine Emmerich, Our Lady also had the full use of reason at that moment and gave herself to God.

The mystics aren’t infallible but the definition of the Immaculate Conception in Ineffabilis Deus IS dogma and must be believed by every Catholic.

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I don’t believe the church declares anything about the timing of ensoulment, but please quote if you have a reference.


" Does anybody agree with me that it is time to put these lame “ensoulment” arguments to rest? Forever?

Now, I should say here that it is true, the Church has not yet infallibly spoken on the matter of “ensoulment” at the moment of fertilization. But that does not mean Catholics are free to speculate either. The Church does teach, at the very least at the level of the Ordinary Magisterium, that “ensoulment” occurs at the moment of conception. There is no human being without a human soul. And there is no human soul joined to a body that is not a human person."


I was not making any argument, just stating what I understand to be true.

Could you quote where that is taught?

My understanding is that she makes no statement on that issue, and makes no requirement about ensoulment as a prerequisite for the protection of the unborn.

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The text in my reply was a quote pulled from the link I shared. I wasn’t asking you that question. Sorry if that wasn’t clear. The answers to your questions are explained in the article.

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The Church has never defined the point of ensoulment. If the blastocyst is not ensouled until the moment they become a fetus, that does not take away from the humanity of the blastocyst.

We respect dignity of human life from conception until natural death. Simple


Which I’ve read.

It looked as if your point might have been that “human being” has to be distinguished from “part of a human being” (for example, “human hand”).

Then the obvious point would have been to point out that this “human” part stays.

But that last sentence seems to be incompatible with this interpretation.

Then the answer is that yes, if in the Petri dish we have something “grown to be a twin of an already existing child”, and everything is going according to the plan, then we have a developing human being in a Petri dish.

“Animal” is a material substance that, according to its essence, is sentient. If it would have no cells, but something else, then it would still be an animal.

If it would not be material, it would not be a human, but, perhaps, an angel.

Well, presumably it is not “a few cells”, as in isolated cells. It is an organism. And it is an organism that, if everything goes right, tends to develop into a adult human, in whom rationality will be clearly seen.

And thus it is a human being.

Your argument fails if there is are essences, and not just individual things. And, of course, there are essences. Which is why biologists can talk about species.

Sure, they are far from knowing enough to delineate one species from another with perfect precision, but we are not in a hurry.


In conception, God chose to have life brought about. I see it as not my choice to take away that which God chose. Who am I to make life/death decisions for God? Some of those won’t make it to birth, but that is also by God’s will, and not my own.

So far as I’m aware, there’s no official position within the Catholic Church on the moment of ensoulment.

Q. If there is a being, which is not composed of animal cells, but is able to think and act rationally, would that being become an “honorary” human?
A. No, it sounds like an android with no immortal soul.

after thoroughly reading Abrosz’ post, really sounds like he’s trying to make a creature like out of the Book of Apocalypse (Rev 17:8/17:11). The Beast…

What does that have to do with my original statement? Catholics are to understand that from the moment of conception there is a human being with a soul who is a person with human rights, most importantly the right to life.

It does take away from it’s humanity because without a soul, it’s not human.

Is the article incorrect? The conclusion points state

2. From the moment there is human life, then, at the moment of conception, there is a human soul, a human being, and a human person.

4. Not only is the necessary conclusion to all of this that the human being that comes into being at the moment of conception is a human person, but this is the teaching of the Church. The idea of a “pre-ensouled” human at the moment of conception “becoming” a human person at some later time is contrary to Catholic teaching.

If we want to quibble over words, I guess I should have written “The Church teaches this is at least at conception.” I will grant you and @Rau that.

That’s quite a circular argument. Once we have human life then it necessarily has a soul. And how do we know it has a soul? Because it’s human life! QED

Honest question: Does the soul appear at the point when the egg is injected with sperm in vitrio?

Um, yes, why wouldn’t it?

It’s a bit like a question “Does a structure of two hydrogen atoms connected to one oxygen atom (water molecule) appear if you mix Hydrochloric acid and Sodium hydroxide in garage and not a lab?”. Place does not change anything important here.

Do you imagine “soul appearing” as something “magic”?

I don’t think it appears at all. I just wanted to know what others thought.

Science is clear. A new human life begins at conception. They aren’t “potential humans”.

I am made up of a few cells as well. The number of cells a human has doesn’t determine whether they are human.


And it is possible to do some gene-splicing and split the fertilized ovum into two. This also can happen naturally resulting fraternal twins. Does the scalpel “create” a new human being and a new soul?

The new “being” can come from an in vitro fertilization, or it can be a fully artificial being. Isn’t technology wonderful?

However, it is the decision of the experimenter to stop it when a new organ has developed, or let it continue until a whole organism comes into being. According to your interpretation it is the decision of the experimenter, which decides if the “final product” is human being or not.

Well, not exactly. The original concept came from the Bible, when God has blown the soul into the nostrils of Adam. Later it was updated, and the moment of “ensoulment” was the quickening. Today there is no official teaching on the subject.

Nope… instead of “rest” it needs to be put to “test”. Or, since there is no gadget to measure if there is a “soul” (either material or immortal) the whole point needs to be discarded.

But, seriously, the thread is not concerned with the “soul”. It is purely secular question: “Are a few cells with human DNA make a human being?” And more importantly: "what is a human DNA?

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