Is causing disease, damage, or disorder in an animal intrinsically evil?


The question to be answered in this thread: Is causing disease, damage, or disorder in an animal intrinsically evil? Why?

I’m looking to verify that my moral analysis is correct (short answer: “Yes, because Genesis”), and ascertain whether I have overlooked something. It seems to me that God commanded us to be good stewards of creation. This then is a parallel mission to healthcare, helping the body function as it was designed – we might call it “earthcare”, to help the environment exist as it was designed. There are numerous examples of the parallels we can mention. To name one, just as we seek to avoid toxins in our own body, so regarding pollution.

It seems, then, that just as we ought not to inflict harm deliberately to our own bodies, we ought not to inflict harm on animals (and plants). Killing them for food is an exception for two reasons: One, God explicitly gave us permission, and two, once the animal has died, it does not suffer. We see that even here the principle of good stewardship holds: It is immoral to torture an animal to death prior to eating it, and there is the imperative to kill the animal as painlessly as possible.

The moral analysis, then:
*]God commanded us to be good stewards of creation.
*]By definition, being a good steward of creation means seeking to help nature exist as it was designed, in accordance with its nature, or else to improve it, not in contradiction with its nature.
*]Inflicting harm upon nature is in direct opposition to helping nature exist as it was designed.
*]Inflicting harm upon nature therefore directly contradicts God’s commandment to be good stewards of creation.
*]Thus, inflicting harm upon nature is intrinsically evil.
It seems, then, that common animal experimentation in radiation biology (to lead towards cancer cures) is intrinsically immoral, examples of doing evil that good may come from it, which God has condemned. Examples of experiments on mice and rats include:
*]causing skin damage (radiation burns) on the hind foot to the point where the skin essentially ruptures (causing bodily fluid to leak out)
*]implanting tumors
*]exposure to radiation (to cause cancer, brain damage, or other bodily disorders)
*]inbreeding (to obtain genetically identical specimens or compromised immune systems)
*]life in a cage (from birth to death, either from cancer or euthanasia)
Of course the reasons for these experiments are compelling, but I cannot see how these actions are not intrinsically evil. It seems, then, that morally sound radiation biology cannot proceed from these experiments, and must instead use cell cultures grown in vitro, collect data from patients (human and animal – this could even lead to an increase in veterinary practice and pet care and hence pet quality of life, if embraced in this context), and perhaps other methods. Moreover, we must ultimately accept that God is sovereign and the master of life and death, rather than inflict harm to animals from a desire to extend our own time on earth.

This question is of great importance to me, because I am investigating the effects of charged particle therapy in suppressing metastases after irradiation (metastases account for 9 of 10 cancer deaths): Inbreeding rodents and implanting tumors within them, etc. is basically a standard research protocol, and the most trusted, accurate one since a complete biological system is used, rather than cells floating in a petri dish solution. My research mentor has advised me that others can do the animal experimentation if I am uncomfortable with it, but, obviously, others doing it doesn’t remove the moral objections.

What are your thoughts?


My gut is uncomfortable with the notion of invasive and harmful animal experimentation, but I think you can find possible arguments which permit necessary experiments, most of which revolve around the “greater good” of creation.

This is a good question though.


An excellent question! And compelling theological discussion!

I would certainly agree that there are theoretical levels of experimentation that are wrong, however nothing in the list you have described comes off to me as intrinsically evil. One key thing you are forgetting is that we are STEWARDS of the world as well as our own bodies. That means we HAVE to experiment to understand better how to properly take care of the world. Here’s a key point to remember - a being is happiest when it is serving it’s purpose. An animal’s purpose (generally) is to serve man. Therefore even an animal being experimented on is in a happy state provided it is serving the purpose it was originally created to do.

Of course, this does not imply that we can do whatever we want. We must have sufficient justification for said experimentation. Perhaps we’re testing out a new cure for cancer, or trying out a new drug to help solve hunger, etc.

In any case - an interesting topic! Thanks for posting!


The Catechism says:

2417 God entrusted animals to the stewardship of those whom he created in his own image.197 Hence it is legitimate to use animals for food and clothing. They may be domesticated to help man in his work and leisure. Medical and scientific experimentation on animals is a morally acceptable practice, if it remains within reasonable limits and contributes to caring for or saving human lives.

2418 It is contrary to human dignity to cause animals to suffer or die needlessly. It is likewise unworthy to spend money on them that should as a priority go to the relief of human misery. One can love animals; one should not direct to them the affection due only to persons.

God bless, V.


My first thought is that the poll is completely disconnected from the thread. :confused: To that, I voted whatever it costs, but here is why: Get yourself pet insurance and never make the decision financial again.

I agree completely with 1newcatholic. I don’t like experimenting on animals, I LESS like the fact that health care research stops without it. Period. End of story. This is a “greater good” argument, and I’d be comfortable with being a cancer researcher who had to irradiate some animals. Treat them with dignity and respect as best you can, but the work is important.


Years ago I toured the Oregon Regional Primate Research Center, now known as the Oregon National Primate Research Center. It is funded by the National Institutes of Health.

While monkeys were in smaller cages, they appeared to be well cared for.

The Center has been the source of a good bit of “pot stirring” by PETA, and my personal take is that PETA has an emotional and (I hate to use the word here) “intellectual” bias that in essence raises animals to at least equal to humans in “rights”.

In my book, PETA has zero credibility, because negative credibility seems to me an oxymoron - but I would willingly go there if someone else chooses that path.

Animals are part of God’s creation; as we are told by the Bible that we have dominion over them (and all the rest of creation), we have a duty to treat what God has given us as the gift that it is. And as a gift, it does not by that fact become equal to or greater than we are in terms of rights.

Out here, some years ago, PETA made a night raid on a mink farm, releasing all of the minks - most of which died not long after that from starvation and predation by other animals. Their objection? The minks were being raised for their pelts.

One can get into all sorts of convoluted “moral” arguments about that; but the mink were well fed and well cared for as their care and feeding has a significant impact on their pelts.

Furthermore, mink carcasses are among some of the best bait for crabbing; so it is not like they are being wasted.

Do I want to raise mink? Not particularly; they can be very vicious and are known for their habit of biting any hand that gets near them. Their life in the wild certainly does not tend towards long survival by many as predation, among other issues, tends to keep them well in check. But then PETA certainly felt they were justified in having the mink die by starvation and predation, rather than being harvested for pelts.



By its nature an intrinsically evil act can never be a morally acceptable practice. Under any circumstance.

CCC 2417 explains (using your expressions) causing disease, damage, or death to an animal can be a morally acceptable practice.


So far, none of the responses have refuted my argument, or identified an error to be corrected. Responding to the two points that have been raised:

  1. CCC 2417 does not contradict my position; rather, it supports it:

God entrusted animals to the stewardship of those whom he created in his own image. Hence it is legitimate to use animals for food and clothing. They may be domesticated to help man in his work and leisure. Medical and scientific experimentation on animals is a morally acceptable practice if it remains within reasonable limits and contributes to caring for or saving human lives.

The second condition is fulfilled, but the first (highlighted here) is not. Whether it is “reasonable” is a qualitative question, but one that I think can be answered easily: It is reasonable to perform experiments on animals such as having them navigate a maze, interact with puzzles, seeking to correct a pre-existing condition (such as pet cancer or birth defects), etc. It is unreasonable to harm them, e.g. causing their skin to rupture or giving them brain damage. (Likewise, forced inbreeding is obviously unreasonable as it contradicts the sexual order instituted by God.)

This leads to the second response:

Here’s a key point to remember - a being is happiest when it is serving [its] purpose. An animal’s purpose (generally) is to serve man. Therefore even an animal being experimented on is in a happy state provided it is serving the purpose it was originally created to do.

This response raises two points to be addressed:

  1. An animal’s purpose is to serve man, yes. However, this service is intrinsically linked to its design, as a horse may pull carriages, or an ox plow fields. It is not clear that animals are to serve men as deliberate proxy victims, a la “It’s wrong to cause brain damage in a human, so we’ll do it to an animal instead.” If animals are to serve as deliberate victims, this must be shown, not assumed. (I say “deliberate victims” because it is clear that animals may serve as unintended, accidental victims, such as monitoring and collecting data after the BP oil spill, or after the Fukushima nuclear contamination.)

  2. You are arguing that an animal’s status justifies its condition, as in theodicy: “It’s okay for you to suffer if your suffering leads you closer to God.” The problem here is that it’s not clear what states animals have, and, moreover, you haven’t shown which state is characterized by being a deliberate victim, from the previous point.

States of man include: being in communion with God, being separated from communion with God. It seems then (generalizing from this) that states of animals include: Existing as they should, and existing as they shouldn’t. Examples of the former state include existing in the wild, being raised on a farm, serving as seeing-eye dogs, carriage pullers, baggage carriers, maze/puzzle solvers (for research purposes), serving man’s leisure (pets) – actions which they are capable of performing with bodily integrity.

I do think this is a key issue: Bodily integrity. It is at the heart of why pollution itself is wrong: The earth has a right to the integrity God gave it. God made everything on earth embodied, and its body defines its nature, and this defining aspect of the body is what demands its integrity. Thus, violating this bodily integrity puts the animal in the category of “existing as it shouldn’t”, rather than existing as it should, so the animals in the practices I’ve described are not in a happy state after all.

(PETA was mentioned as releasing animals from cages. There is a point where a cage can infringe on bodily integrity, but this is determined by the circumstances and the animal’s needs, so a mouse may reasonably spend its life in a laboratory if all its needs are met.)

If I have made an error, please identify and explain it.

Finally, research would not cease if these practices ceased, as I went out of my way to explain in the OP (please read it again), and we can experiment with animals without deliberately harming them, such as through providing pets experimental cancer treatments.


It does if you misuse the term intrinsically evil. It is important we use such terms appropriately.

For example, Abortion is an intrinsically evil act. Intentionally killing the innocent unborn is always evil by its nature and can never be moral under any circumstances.

On the other hand, killing an animal can be a moral good (i.e., food - clothing). We can see evidence of this moral good when Jesus directed the fishing nets cast to catch an enormous amount (John 21:6).

I do agree (as most should) it is disordered to make an animal suffer or kill them without reasonable cause.

CCC 2418 It is contrary to human dignity to cause animals to suffer or die needlessly. It is likewise unworthy to spend money on them that should as a priority go to the relief of human misery. One can love animals; one should not direct to them the affection due only to persons.


Dent, you seem to have not followed carefully what I’ve said. I didn’t say “anything we do to animals is intrinsically evil,” as if all experiments were. I even gave examples that weren’t, such as mazes and puzzles. I implied these specific actions are:

As the Catechism implies, as we’ve both quoted, these are not morally licit insofar as they are unreasonable.

Moreover, at no point did I ever even protest the killing of animals (I said words even to the opposite), so it really looks like you haven’t been reading carefully enough.


I see. In this case, it would be judicious to reframe the original question.

The question to be answered in this thread: **Is causing disease, damage, or disorder in an animal intrinsically evil? **

The principle of good stewardship can be examined without muddying the waters (so to speak).

One can implant a tumor into a mouse in efforts to forward our understanding of medical treatments designed to save human beings. There would be nothing intrinsically wrong in this action.

If one implanted a tumor to watch an animal suffer for entertainment purposes this would be a sinful offense against God by disrespecting the natural environment God gifted us with.

If this is framed improperly it can sow confusion – one becoming more common in contemporary society; where some attempt to bestow on animals the dignity God gave to the human person. When this distortion occurs the risk becomes great in which the objective moral order is denied.


Dent, I’m not sure what the source of your confusion is. I am saying that implanting a tumor is intrinsically evil, because it is causing harm to the animal, violating its bodily integrity. To use the Catechism’s terminology, ‘the experiment is exceeding reasonable limits’. You haven’t given any argument to the contrary.

It seems that you are conflating ‘experiment with animals’ with ‘hurting animals’, so that when you read the Catechism, you think that it is saying, “Hurting animals is morally permissible if it remains within reasonable limits.” That is not the meaning of the text. An experiment is simply a trial where some facet of nature is investigated. Hence, having a mouse run through a maze to obtain a piece of cheese is an experiment. “Animal experimentation” does not imply the animal is always hurt.

Thus, when the Catechism says “Medical and scientific experimentation on animals”, it is speaking generally about any investigation of science or medicine that has animals as their subject. An example of such an experiment that is within reasonable limits would be providing a diseased pet experimental therapy, as I’ve said multiple times already. The question here is whether causing cancer within an animal, etc., exceeds what is reasonable to do to an animal.

Incidentally, I could provide photographs of what the animal experiences to help clarify the matter. Like Fr. Frank Pavone has done with feticide (showing photographs), often people don’t realize the evil that occurs because they don’t see it, and instead think about it abstractly and unclearly.


The act of causing harm and violating bodily integrity of an animal is not an intrinsic evil since such a claim would make the very nature of that act unacceptable under any circumstance. Thus denying some uses of animals and the natural environment and a part of its purpose. There are reasonable conditions where this destruction of bodily integrity can be necessary.

The standard you are trying to apply would require a new creation to be manifested. One where an extreme principle of preservation could not to be violated.

Yet we know by divine revelation preservation is not the purpose for animals and the natural environment. Man was given the gift of animals and the natural environment for good use. It falls within its purpose. Yet we do know this use is not an absolute. We need to avoid abuse and waste.

For medical experimentation on animals to be reasonable this would require weighing the potential outcome of the research and avoiding abuse (what is the end?) . At times, harm and death to animals could be a consequence of research. To avoid abuse in such medical research, a necessity need exist to help save human lives where a serious gap currently exists. And mindless cruelty needs to be avoided. One should always treat creation with respect.

For example, some years ago - monkeys where used in medical testing with Ebola. It was necessary to intentionally expose the animals to the disease to find how the infection spread. Animals perished. The goal of the experimentation was not to see how Ebola killed animals but to gain critical understanding of a disease capable of jumping to a human population. The end was the safety and saving of human lives. Such testing still requires man to avoid unnecessary suffering - as much as possible.

This use would not constitute an abuse. It falls within the general purpose God gave us nature.

There could also be reasonable and ethical testing done where animals are sacrificed to learn how to save an ecosystem when one is under threat. This use requires ethical analysis.

But we still need to analyze the means. Do we always need to use animals? Can current testing be done successfully without the suffering, destruction and death of animals? Do we only do such acts because they are economically attractive? These are important factors as well.

(On the flip side)

IMO, Tad Pacholczyk (a neuroscientist who writes articles in the field of bioethics) offers a good example of an abuse of animals. In the realm of food production.

The example is of foie gras. The animal being diseased and experiencing considerable suffering for what end ? His conclusion: “the production of foie gras is instead oriented toward the satisfaction of a disordered desire, a disturbing desire to satisfy the human palate to the point of promoting serious animal mistreatment.” I agree with this assessment.

The use of animals and the environment is not an absolute.


Dent, I think one source of your confusion is that you focus on certain phrases too literally, not noticing the context and nuances of the whole message. Thank you for your responses; I don’t think there’s anything more to be said between us. Your response has been, “The end justifies the means,” and I must continue to think that you are wrong, because you have yet to make any explanation on how the means are not intrinsically evil.

I am also disappointed with the forum members here. I have received hardly any responses, and those I did receive presented no new information, whereas I was hoping to be proven wrong.


Thanks for the discussion.

It is evident you mean well but you have a deficient understanding of the term you have used which negates any serious penetration of the area of discussion. Best move on to another question.


I don’t understand how your poll relates to your question. Cancer is not caused by doing damage to an animal. Nobody knows what causes cancer.


Christine, the poll and the thread discussion are only tangentially related. Don’t think a poll must always follow the discussion of a thread.

And, Dent, I have not misunderstood what ‘intrinsically evil’ means. I am asking you to show how deliberately hurting an animal isn’t intrinsically evil, and you have not done so.


The analysis is flawed.

God commanded that harm be inflicted on animals deliberately as part of the Old Testament sacrificial system. God does not command evil.

There are other flaws in the understanding of what stewardship is, understanding of the word intrinsic and the nature of animals as they were designed, but God’s commandment to deliberately kill animals is argument enough.



Actually, it does not.

To kill an animal would be, of necessity, to damage it.

But it is not an intrinsically evil act to kill an animal.

Nor, for example, would it be intrinsically evil for an animal to be anesticised, a wound inflicted on it, and then have a paramedic or medical student, for example, practice life saving manuvers on it. Afterward, the animal could be euthanized, so it experiences no suffering.

That too would not be contrary to reason, and would contribute to the saving of human lives.


Good point about killing animals, namely, I didn’t realize that killing would be included in ‘damage’. Okay, so I must rephrase my question: Is causing disease or disorder in an animal intrinsically evil?

No one has been able to justify the examples I gave, e.g. about implanting tumors or causing brain damage.

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