Preventative Medicine Can Be Ordinary Means

I thought it was fairly obvious that preventative measures can be ordinary means, but Daniel O’Connor tried to make the argument online to the contrary. This will include all his original post, and some back and forth. I’ll cover my tweet, his main argument, a non-existant distinction and wrapping up the other minor points of his main tweet. After I wrote the first draft, he posted a reply with a bunch of untruths where he actually nullifies his argument.

This began when I posted that vaccines were ordinary means based largely on Carson & Flood, & McTavish & Eberl. Both papers effectively argue that recommended vaccines are in most cases ordinary means and thus generally morally obligatory.

I think this follows as necessary conclusion of a Catholic understanding of ordinary means, which Pius XII referred to as “Means that do not involve any grave burden for oneself or another.” A 1958 moral theology manual noted that ordinary means are those that “offer a reasonable hope of benefit for the patient and which can be obtained and used without excessive expense, pain, or other inconvenience.” With definitions like this, most normal immunization vaccines are evidently ordinary means. Vaccines recommended for the whole population consistently have a reward thousands of times their risk/burden: in the scientific community, this is not a debated point. I explain myself further here.

My Tweet That Started it All

So, I posted this,

There were a lot of replies just affirming the opposite without a serious attempt at an argument or a serious dialogue with ordinary vs extraordinary means. One person, Daniel O’Connor tried to make a new and innovative argument against this. I congratulate him on the creativity for thinking up the argument, but it fails.

Daniel O’Connor’s Main Argument

He quote tweeted me with this lengthy tweet (I will cut it up for a response):

Woman after flu Vaccine (CC0 CDC on Unsplash)

Fr. Schneider’s entire argument that the Covid jab is a “moral obligation” rests upon the (false) premise that it is a “treatment” and thus qualifies as morally requisite “ordinary care.” Obviously, however, it is NOT a treatment. The jabs are medical interventions for (it is alleged) prevention. This completely changes the moral analysis, but both he and the scholars he incessantly refers us to ignore that distinction, or at most cite a random and irrelevant opinion of a certain Fr. Gerard Kelly from 1958. In fact, TREATMENT consists of efforts aimed at remediating a health problem *one actually has.*

I never said it was a treatment. I said it was a vaccine, which is a form of preventative medicine.

I just finished scouring many Magisterial documents that refer to the duty to employ “ordinary means” of care in various circumstances. Every single one of them refers to this in the context of THERAPEUTIC methods (i.e., addressing a *present* bodily problem).

This is so patently false. The first line in response to questions about the case of Terri Schiavo (woman who was in a persistent vegetative state & her husband stopped putting food & water in her feeding tube so she died of dehydration & starvation) says:

The administration of food and water even by artificial means is, in principle, an ordinary and proportionate means of preserving life. It is therefore obligatory to the extent to which, and for as long as, it is shown to accomplish its proper finality, which is the hydration and nourishment of the patient. In this way suffering and death by starvation and dehydration are prevented.

First, it lists food and water as “ordinary means.” Second, it explicitly says their purpose is to prevent bad effects, not treat an existing condition or be therapeutic.

The official CDF commentary is even more explicit, avoiding the context of things like feeding tubes: “Nutrition and hydration are to be considered as normal care and ordinary means for the preservation of life.”

A simple search also finds similar statements in 1991 & 1992 by the NCCB (USCCB) & an individual bishop arguing food & water are ordinary means. Showing a consistent magisterium from bishops (albeit not the Pope or Vatican).

The CDF quote and others directly prove his central point wrong.

If his main point were right, that no preventative treatment were ordinary means, that would imply Mr. Schiavo could have starved his wife at least until food became therapeutic to treat starvation. / malnutrtion.

O’Connor Tries to Make a Nonexistent Distinction

Continuing his long tweet, he notes something he will try to make into a distinction later but I did not realize where he would go on first reading:

NEVER, that I have found at least, has the Magisterium referred to obligatory “ordinary care” with respect to *preventative* medical interventions.

He wants to try to say that water & food, despite often being the first examples used for ordinary care, are exceptions. He argues later, “Food and water are not ‘preventative medical interventions.’ (Who on earth has ever called them that?) Vaccines are.”

I don’t call them that usually, but I focused on his prior line and assumed this was more rhetorical repetition. He wants to distinguish “preventative medical interventions” from both other preventative means. However this has several issues.

As I tweeted:

“Preventative medical interventions” never appears in the magisterium or really in medical literature. The magisterium when talking about food & water notes that the same criteria apply if there is a feeding tube or not, so it avoids making any distinction. When talking about when it would become overburdensome & extraordinary, no distinction is made between something like food /water & some kind of drug. So you are making a distinction that is not there, unless you can show me some cases where the magisterium, bioethics or medical literature to make such a distinction.

Further, the Schiavo document above combines feeding by mouth or by feeding tube so seems to avoid distinctions between how “medical” the intervention is. Nowhere could I find this distinction in the magisterium, & I invited him to show it to me.

Further, the magisterium does not seem to distinguish between preventive & therapeutic treatments. It is often the case that in practice this is a gray line anyway. For example, if a person is starving and I start giving them food, at what point does it go from therapeutic for malnutrition to preventative? Or, blood pressure medication at lower levels of hypertension is preventative regarding damage by extended high blood pressure or higher blood pressure; at some point, blood pressure medication is actually therapeutic: we can make an estimation there, but we can’t really perfectly determine where but a precise line is.

Thus, ordinary & extraordinary do not distinguish between medical vs. non-medical or preventative vs. therapeutic. All four combinations of those 2 binaries can be either ordinary or extraordinary care depending on what treatment & what patient.

O’Connor Is Consistent in His Odd Definition

O’Connor was at least consistent. He later argued sunscreen would not be ordinary means “if my doctor tells me that I will likely die young of skin cancer unless I take the relatively easy step of making sure that I wear sunscreen.” O’Connor did not budge if, as his interlocutor, Taylor Patrick O’Neill noted,

it is 1) easy care of the body 2) the side effects are grossly outweighed by the intended effects 3) not doing so directly contributes to the early death of my body, it is still not obligatory?

This is obviously under ordinary means given that O’Neill basically lays it out as fitting the definition in that tweet.

Obviously, this needs a few clarifications implied above: (1) You could also cover your skin, (2) sunscreen need only be applied if going out for an extended period. I don’t wear it walking to my car or riding 30 minutes on a semi-shady road, but there is no way I’m ever going out where I will be over an hour in direct sun and intentionally avoiding sunscreen (I am high-risk for skin cancer).

Quick Notes on O’Connor’s Other Points

Most of the rest of O’Connor’s long tweet:

Fr. Schneider, et. al., are trying to invent a brand new moral law and foist it upon us all, on pain of sin.

We’ve repeatedly noted how our moral theology follows Church teaching and the bioethical / moral theology tradition. O’Connor has instead tried to apply two new distinctions that have never been applied to ordinary vs extraordinary. His argument seems to be more about justifying a position he already had about vaccines rather than a natural outcome of bioethics.

As a note here, I came to this thinking vaccines likely weren’t ordinary care, but as I read up and looked at the evidence myself this conclusion became overwhelming. The exact opposite of O’Connor’s attempt which seems to be more an after-the-fact justifcation.

He continues:

I also read the whole article Fr. Schneider is constantly deferring to. (This one:…) It is astoundingly oblivious. It, too, never even addresses, much less defends, its base premise that vaccines are “treatments.” (Except for, again, noting Fr. Kelly)

This was answered above. He is assuming his distinction that does not really exist. Preventative means can be ordinary means so there is no reason to argue it is a treatment. Such an argument would be false anyways.


It takes the CDF’s very clear insistence that vaccination is NOT a moral obligation and essentially dismisses it by filtering it through a purely personal opinion offered by Pope Francis (one he clarified as a personal opinion by prefacing it with “I believe…”). As if Francis couldn’t just issue his own Magisterium on this if he wanted to overrule or “clarify” the CDF! Three years later, he never has. The CDF’s document remains by far the highest teaching on this. And it contradicts Fr. Schneider, et. al. The article later assures us we’re not really being forced to be vaccinated, since we can just lose our jobs, etc.; no one is tying us down and violently jabbing us! (Wow, what a consolation!) It says the government doesn’t have to respect our consciences because they are “misinformed.” Reminds me of Matthew 10:21 “Brother will hand over brother to death.”

I think it is important to distinguish between types of mandates. Mandating a vaccine for all hospital staff & all people in the country are radically different proposals, as the risks of not vaccinating for a hospital nurse & the night janitor alone in an office building are radically different. I have noted that universal mandates for COVID vaccines are likely not good while hospitals have a moral obligation to ensure immunity of all staff to infectious agents for which vaccines exist. I also noted some things in a commentary on one of the better letters by a US bishop on mandates.

O’Connor seems mad as it is personal: he was removed from his PhD program for refusing to vaccinate. I would take the CDF line regarding vaccines needing to be voluntary as against universal mandates as a rule, but not in any way commenting on the ethics of vaccinating in itself and fully allowing focused mandates like all hospital staff.

Finally, his long tweet concludes:

The real prize for the most absurd statement, however, goes to the other scholarly article Fr. Schneider cites all the time–the 2017 one, “Catholic Social Teaching and the Duty to Vaccinate” from the American Journal of Bioethics, by Paul Carson and Anthony Flood. They said: “There remains an open question of whether the state should be trusted in all things and with all initiatives. We merely contend that in this context, mistrust of the state is not a sufficient reason to refuse vaccination.” Wow. So they graciously concede that whether we should trust the state on EVERYTHING, EVERYWHERE is at least an “open question”! Even if, however–they assure us–there might be SOME conceivable situation in some hypothetical time where we shouldn’t put our absolute Faith in the State, that time is certainly not with vaccination. With that, any such concerns are anathema. God save the Church from scholars hell bent on subjugating it to demonic worldly agendas.

Mistrust of the state is not sufficient to refuse vaccination when there is a whole stack of other evidence in favor. It seems that O’Connor unfortunately makes the error of over-correcting. Yes, when the government says we should allow gay marriage and abortion, we should not trust it, but that need not mean we should always mistrust it automatically.


In conclusion, O’Connor argued that preventative means could not be ordinary means. When that was shown false as the Terri Schiavo case showed otherwise, he tried to make some arificial distinction to argue only preventive medical things cannot be ordinary means. However, when we look at the magisterium or the serious bioethicists I remember, there is no distinction between preventative & therapeutic nor between medical & non-medical regarding ordinary means. Preventative medicine can be ordinary means. O’Connor seems to have started with his conclusion and then worked back to an argument rather than worked out logical conclusions from the magisterium & best bioethicists.

Postscript: O’Connor Decides to Speak Untruths

O’Connor came back with a reply after I wrote this but before I clicked publish. Here are some parts that are untrue.

Fact 1: Therapeutic treatments & preventative medical interventions are fundamentally different things. Referring to one does NOT indicate the other is also included in the reference. You and the authors of the scholarly articles you quote fabricated, out of whole cloth, the notion that they are identical to construct your argument–an argument which, recall, the CDF has rejected.

Yes, they are different but this does not imply only one can be ordinary means.

He claims the CDF has never rejected this – I asked for sources & he came up empty. If he can find the quote here, I am open to modification. The CDF has never directly & definitively stated that preventative & therapeutic interventions can both be ordinary means, but it implies this in treating the removal of both the same as possibly extraordinary or other times it speaks of ordianry & extraordinary.

The Magisterium only refers to general (universal) moral obligations in the case of certain therapeutic treatments of actual (that is, present) serious health problems (and even then, it only does so in some extreme cases; usually with respect to end of life care).

Moreover, the Magisterium never will teach that any aspect of preventative medicine (i.e., medical interventions designed solely to hopefully circumvent some possible future issue) is a universal moral obligation, as this would contradict Our Lord: “Those who are well do not need a physician.” Luke 5:31

(Food, water, etc., are neither therapeutic nor preventative; they simply are not medical interventions at all; they are the obvious basic requirements of life and have nothing to do with our point of contention. No one in his right mind has ever referred to food as a “preventative medical intervention.” That is just absurd.)

This is a change from above about food & water being preventative. The CDF has explicitly ruled that food and water are preventative in the Schiavo response quoted above. So, his claim is directly contradicted by the CDF. The CDF commentary makes it clear that these are general moral obligations not just in specific cases.

O’Connor tries to argue somehow these are categorically different when dealing with ordinary vs extraordinary care. Yet, in all the magisterium I’ve read & the best theologians on this, I have not seen anyone distinguish “medical” & “non-medical interventions.” In fact, this would get complex as the division between these two gets blurred: is IV nutrition and fluid for a few days medical or non-medical, is using a feeding tube medical? The Schiavo response explicitly said using a feeding tube which is at least somewhat in the medical direction versus mouth-feeding is less medical.

O’Connor is just repeating his distinction without evidence that it has any bearing on ordinary vs extraordinary & with concrete evidence pointing away from it being relevant in a way that would make preventative medical actions always extraordinary.

There are a thousand reasons to be deeply concerned about their side effects. They are completely experimental; the mRNA jabs can even be fairly called experimental gene therapies. And yes, they are abortion-tainted (that too is a fact). They likely don’t even work and perhaps even make you get Covid worse. But besides all that, the chance of dying from Covid is utterly miniscule, and there are plenty of ways to ensure one doesn’t spread it if he gets it.

So he decides to conclude with a bunch of scientific misinformation.

He claims they are “completely experimental” which has not been a generally accurate term since late 2020. Once they have an EUA (December 2020) interventions are not usually considered “experimental.” Although some can push this to full approval (mid 2021); but adding “completely” at this time is inaccurate.

“The mRNA jabs can even be fairly called experimental gene therapies.” Given how insistent he was on distinguishing therapies or therapeutic means from preventative ones, it seems odd he switches to therapy here. COVID vaccines are not therapies as they don’t treat an existing disease, but given what he said above, his term now pushes vaccines back into what can be considered ordinary means by his inaccurate analysis. His redefinition of vaccines nullifies his main argument.

Gene therapies are defined in the Merriam-Webster medical dictionary as “the insertion of usually genetically altered genes into cells especially to replace defective genes in the treatment of genetic disorders or to provide a specialized disease-fighting function (as the destruction of tumor cells).” This is so far off from what covid vaccines do as to be laughable.

If the US covid vaccines are “abortion-tainted (that too is a fact),” then everything with Chinese-made parts far more is abortion & genocide tainted as it funds their forced abortions & Uigjur genocide. Now it is virtually impossible whatever O’Connor used to make this has no parts made in China, so he is contradicting his argument for avoiding “abortion-tainted” things by the mode he makes the argument. If people want to use “abortion-tainted,” they should use it at least somewhat consistently, not to filter out a gnat while swallowing a camel.

The evidence covid vaccines work is overwhelming. People are about 1/3 as likely to get covid and about 1/7 as likely to die from it if vaccinated. This may have gone down a bit but 60% less likely to be infected & 80% less likely to die are still working.

He claims “the chance of dying from Covid is utterly minuscule.” It is not 30% like smallpox or something, but it is much greater than many diseases we’ve been vaccinating against for years. & it was agreed by moralists that Catholic schools could morally require these prior vaccines.

He states, “there are plenty of ways to ensure one doesn’t spread it if he gets it.” The issue is that spread is most likely to happen when you first get it before you have symptoms that put you in bed. If you have no symptoms, you likely won’t spread it but if you later develop symptoms, you can spread it in that time just before they develop. That is how I got covid from a member of my community back in late 2020. Unless you are pretty isolated in your life from others, it is hard to maintain a degree of isolation in case you get it on the regular.

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  1. FYI: comments are on approval. I generally approve most even stuff that I disagree with. However, when people share off topic stuff or pseudoscience I don’t want to dedicate time to rebuking, it gets deleted. I don’t want other readers confused.

  2. Portions from the comments I made responding to this on Twitter are below. I’m not planning on further engaging this, although I’m certain Fr. Schneider will continue it. I would simply encourage all, despite whatever he says next (which will likely simply be a rephrasing of what he says here) to trust the CDF over Fr. Schneider. The CDF has taught that vaccination is NOT a moral obligation.
    God bless you!
    In Christ, through Mary,

    [This article] essentially does nothing but pretend there’s no difference between purely preventative medical interventions given to hopefully avert a possible future issue (such as vaccines), and, on the other hand, therapeutic treatment properly speaking (such as basic medicines needed for one dying of an easily curable bacterial infection.)

    [Fr. Schneider] offers this fiction in contradiction to common sense, the standard use of language, the CDF, the Magisterium in general, and above all Jesus Christ: “Those who are well do not need a physician.” Luke 5:31.

    And to those wondering if he accomplished the task I suggested in my last tweet, the answer is no. He provides no examples of the Magisterium ever imposing a general moral obligation to undertake purely preventative medical interventions. The reason is clear: no such universal moral obligation has ever existed, or ever will exist.

    Instead, he repeats his utterly bizarre insistence that food and water are actually preventative medical interventions, and that since food is always morally obligatory, so are vaccines. (This is too insane to waste much time refuting, although I’ll note that the quote below from the CDF contradicts him.) And he repeats his condemnation of me for thinking you aren’t going to hell for passing on the sunblock.

    “Nutrition and hydration do not constitute medical therapy in a proper sense, which is intended to counteract the pathology that afflicts the patient.” —Congregation for the Doctrine of the Faith, 2020. Samaritanus bonus. (I don’t know where Fr. Schneider gets the idea that this distinction isn’t in the Magisterium. In fact, the Magisterium constantly specifies when its bioethical teachings are referring to therapeutic methods [which vaccines never are.] And, again, it never universally obliges purely preventative interventions. )

    *** 2nd Tweet:***
    My purpose with the Samaritanus bonus quote was to point out the obvious truth (which I should not have needed to show Magisterium to prove to anyone who speaks English, but you insisted) that food is not a medical intervention of any sort (neither therapeutic, as S.B. focuses on, nor preventative), therefore it has nothing to do with our discussion. Yes, Schiavo was murdered–because she was starved. The feeding tube (etc.) was the therapeutic medical intervention, and that was placed to TREAT the PRESENT PROBLEM of her inability to naturally eat sufficiently well on her own. It was obviously NOT a purely preventative medical intervention. It is also equally obvious that feeding her, through that tube, was not a purely preventative medical intervention. It was basic nourishment necessary for life. Therefore, this move you attempt is entirely irrelevant to the matter at hand.

    Also, you mischaracterize my argument almost every time you refer to it. I am NOT saying “prevention can’t be ordinary.” Clearly, vitamins, for example, are quite “ordinary,” you could say. I am saying purely preventative medical interventions cannot be universal moral obligations. Your entire argument that the Covid jabs are general moral obligations hinges on THAT (utterly fallacious) premise, which you can’t even pretend to justify except with bizarre claims that equate vaccines to food. Your entire article, therefore, is a non sequitur.

    1. My reply to his first tweet (as tweeted):
      Your one new line is “Nutrition and hydration do not constitute medical therapy in a proper sense, which is intended to counteract the pathology that afflicts the patient.” from Samaritanus bonus

      I read it but did not remember it precisely. But here, therapy is defined as treating a disease (i.e. not preventative); it is not defined as being medical or non-medical. Lines around that line uses terms similar to calling this non-therapy “ordinary means” although that exact term is not used.

      My point on the lack of distinction was not that it never made it – the Schiavo response also noted these were preventative – but that no distinction was made to them in regard to ordinary & extraordinary such that one could argue preventative, “non-medical,” or the combination of the two somehow cannot be ordinary means.

      Then you say “it never universally obliges purely preventative interventions.” Shall we return to the Schiavo response: artificial feeding which can be considered an “intervention” in a way (given mouth feeding is the normal way to get that) was universally obliged for PVS patients.

      My reply to his second tweet (as tweeted):

      Maybe I was not as clear but I viewed your way of analyzing it as making a square of four with one side being prevention / therapeutic & the other being medical / non-medical (below). Of the four options, you seemed to argue that only the preventative medical could not be ordinary means (2, 3 & 4 could be ordiany means but not 1). The Schiavo letter clearly shows that preventative is allowed but you would class that as non-medical (2).

      Like this:
      —————- Medical Non-medical
      Preventative 1 2
      Therapeutic 3 4

      My point is that the magisterium never makes a medical / non-medical distinction like that talking about ordinary / extraordinary means, and approves both preventative & therapeutic means treating them similarly when they deal with them (like removing food & removing therapy in one’s last hours once futile).

      Your argument here is that food & water were are non-medical, and claim samaritanus bonus says that. That is not what it says: It says it is not therapeutic: “medical therapy in a proper sense, which is intended to counteract the pathology that afflicts the patient.” this leave open it being either of the other two options: preventative non-medical & preventative medical.

      I don’t object to some use of the terms, I don’t see anywhere the magisterium restrict any of the 4 from being ordinary means & all evidence points the other way.

      As yo and I both kind of agree this is too time consuming, I’ll just copy this tweet as a comment on my article then we’ll lay things to rest.

  3. There was no safety testing for the covid vax. Biden told you straight out that as soon as China gave us the DNA breakdown of the virus they made the vaccine and released it to the public. You are the last person who should be giving medical advice. I’ve worked decades in hospital medicine. You are highly unqualified to speak

    1. You may want to check actual data & peer reviewed studies before making comments.

      The vaccine was first created in early 2020 (I think January), yet it was only approved in Decemebr 2020 under EUA & mid-2021 fully. You know why there was a delay? The biggest reason is safety trials, although sthe same trials also showed its effectiveness.

      Given your first line about no safety testing, I highly doubt your later one, “I’ve worked decades in hospital medicine.”

      1. Father,

        I don’t think we can doubt her credentials, there’s a wide variety of opinions on this in the medical field. One year does not constitute a long term trial with exhaustive controls, I think we can both agree on this and safely state that this medical intervention had far less time in testing than previous medical interventions.
        I think the more interesting point is to be made about the Magisterium, because informed consent is integral to consenting to medical experimentation. I’d like to understand your position a little more carefully and fairly assess the position you hold. Let’s look at the following propositions:

        1) A pregnant woman is told to take the COVID-19 intervention and is told it is “safe and effective”. (We both knew that the CDC doesn’t actually recommend many vaccines for pregnant women) Does she have moral liberty to decline? (real case, my wife one year ago)

        2) Someone has repeated bad experiences with medical experimentation (as a child and young adult when I had no liberty to decline) or other interventions and simply does not trust the medical field whatsoever. Does this individual have moral liberty to decline? If not, what is his culpability? (This is my situation)

        I think these two cases highlight some potential issues for your position in the Magisterium.
        If you get around to this I thank you for your time, I understand not everyone interacts in good faith or respects the office of the priesthood sufficiently. I think you’re a man trying to make it to heaven and trying to guide is flock. I do NOT think you’re a heretic, an evil globalist, a conspirator or anything but instead want to be precise and understand your position in relation to the Church’s teaching.


        1. Her first line: “There was no safety testing for the covid vax.” Anyone who worked decades in a hospital as medical staff should be able to recognize there was safety testing. If she were to argue “There was INSUFFICIENT safety testing for the covid vax.” that is an opinon someone in a hospital may hold. For an argument of insufficient testing you need to show some test on humans not done for the covid vaccine but done for other relatively recent vaccines, like say Chickenpozx that was only approved in the 1990s. Can you name a safety study that was doen for that whcih was skipped in the covid vaccine. I went through the FDA approval documents for the Chickenpox vaccine & could not find one.

          Your two cases:
          1. As your wife was in mid to late 2022, we had studies about pregnancy risks well before then. We did not have these when first approved in December 2020 & pregnant women were not recommended to get it then.
          2. I have not heard of a peron repeatedly used for medical experimentataion, when the first was bad unless they had soem rare serious disease paretns were trying some new treatments on. The only other way I see htis case making sense is if you have a definition of medical experimentation way off the normal to the point it’s fundtionally meaningless.

          This is a littel off topic of the post now.

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