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Moral Intuition, Logic, and the Abortion Debate

Moral principles must be based on pre-logical moral intuitions and laws should be based on those moral principles. (Of course, to say that “laws should be based on those moral principles” is not to say that every moral principle should automatically be enacted into law.)

Though everyone I have talked to agrees that moral principles must be based on pre-logical moral intuitions, I have heard an intelligent person or two contend that the correctness of such moral intuitions can still be logically proved or disproved – as if moral inquiries were a hard science like math. More importantly, many people who would not explicitly make this contention nevertheless present their arguments about moral issues as if this were the case. So while some philosopher probably demonstrated centuries ago the impossibility of logically proving the correctness of moral intuitions, the relationship of logic and intuition still deserves to be examined. And I think the insights gained in the process of examining it might change how we converse, including how we converse about abortion.

First of all, for moral principles to be based on moral intuitions really means that moral principles are the verbalized form of moral intuitions. Therefore, correct moral principles will follow from correct moral intuitions. And if the correctness of a moral intuition could be logically proved, then it would be possible to construct a correct moral principle through logic alone, with no recourse to intuition – since the process of constructing would be the same as the process of proving.

To say that it would be possible to construct a correct moral principle through logic alone but at the same time to agree that moral intuitions (of which moral principles are the verbalized forms) are pre-logical – as everyone seems to agree – would be contradictory. Nevertheless, as mentioned, some people do present their arguments about moral issues as if the correctness of a moral intuition could be logically proved (that is, as if it would be possible to construct a correct moral principle through logic alone). So let’s continue to address that contention.

“The correctness of a moral intuition can be logically proved” and “a correct moral principle can be constructed through logic alone” seem to me like two different formulations of the same thing. But in case there’s any doubt, as I continue I’ll address the former, which is the one I’ve actually heard.

Is there such a thing as a correct moral intuition, and if so, can its correctness be logically proved or disproved? Though I am arguing no to the second question, I will argue yes to the first.

Moral Intuitions and Moral Principles

As an example of a moral principle – a generalized moral principle, but basically a sound one, I feel – let’s use “Thou shalt not kill.” I would say that that principle did not come from God but rather is based on a pre-logical and pre-verbal human revulsion at most killing of the innocent. A pre-logical and pre-verbal sense of right or wrong is how I would define a moral intuition.

Psychology professor Paul Bloom, author of the recent book Just Babies: The Origins of Good and Evil, said in an interview that while some moral ideals “are the product of culture and society” and “not in the genes,” “there also exist hardwired moral universals – moral principles that we all possess. And even those aspects of morality . . . that vary across cultures are ultimately grounded in these moral foundations.”

Even if Bloom overestimates the role of the genes in the “hardwired” moral senses and underestimates the role of culture in those moral senses and also overestimates how universal those moral senses are across cultures, it would be safe to say that most of us do have senses of right or wrong that come out of our unconscious in ways we cannot understand. I am calling those senses moral intuitions.

I would say that the pre-logical and pre-verbal human revulsion at most killing of the innocent is an example of a correct moral intuition. I call it “correct” in that I think that deference to that intuition is necessary to the psychological health of human beings. I think that humans will sacrifice some of their psychological health (their conscience will trouble them, if you will, and they will carry around guilt, sometimes at a subconscious level) if they go against that intuition. I think that such psychological health could be measured, but let’s call the idea of measuring it just my idea, for now.

If we can accept that we are born with at least the seeds of some moral intuitions in us, then clearly those seeds are in each of us before we begin thinking logically, just as the emotions of babies are. Moral intuitions and emotions develop in us before logic and continue to function in us pre-logically; science and logic develop in us later.

Moral intuitions and emotions are both forms of caring. Science and logic operate under certain rules, one of which, for both, is a commitment to dispassion. So science and logic can tell us, in their different ways, what is, but they cannot tell us the meaning of life or convince us to care about anything. And since they cannot convince us to care or convince us that anything matters, they cannot tell us what should be. Only moral intuitions, which are a form of caring, can tell us what should be – can give us moral principles.

Logic cannot even prove to us that right or wrong exists, much less that any action is right or wrong. So of course it cannot prove that the moral intuition that told us how to act is right or wrong, correct or incorrect. Logical thought aimed at setting moral principles is impossible without basing it on something pre-logical.

Logic can be applied to intuitions, but as a dispassionate science, it can only demonstrate the correctness of any moral intuition, if at all, with reference to some already-existing moral intuition. Tracing back in this way, we will eventually come to some moral intuition that was not arrived at through logic. It came out of our unconscious in some way we cannot understand.

Finally, the medium of logic is either words or math, while an intuition is by definition something pre-logical (and pre-verbal and pre-mathematical). Since an intuition is not framed in words or math, words and math cannot completely describe it, much less prove it right or wrong. Logic may lead us close to the door of intuition—with luck very close—but in order to pass through and feel the intuition, feel that something matters, we have to leave logic behind. As mentioned, it is only the intuition that says, “Something matters,” not the logic.

We should never say, “I believe in XYZ principle for ABC reasons,” but rather, “I intuit that XYZ principle is correct, and A, B and C are likely the factors that brought me to that intuition.”

The foregoing means that all of us involved on any side of the abortion issue, as with many issues, are out advocating or marching or voting for policies that mean life or death for others, without completely knowing why we are doing so. (This does not mean that we should fail to proceed as best we can, however.)

I recently came across a thought experiment created by Jake Earl that offers an analogy to pregnancy and abortion:

While on a hike one morning in the Appalachian wilderness, John hears the screams of a child coming from the nearby river. He sees the child is clinging to a rock in the middle of the river, and will surely die without his assistance, since nobody else is around to help and John does not have the means to call emergency services. John is a decent swimmer, so he will almost certainly survive the rescue attempt, but there are still risks: the polluted water threatens to worsen John’s health in the near- and long-term, he will likely experience significant pain and discomfort in getting the child out of the river and getting him to safety, and the whole experience might be so traumatic as to send John into depression, and might damage his overall quality of life. Also, even though John is a swimmer, the river is tricky, and he faces a fundamentally unknown risk to his life if he embarks on the mission.

Now, is it obvious that John is morally obligated to do everything in his power to keep the child alive? Perhaps he [is], but I think it is in no way obvious, precisely because common sense tells us that the duty to rescue others is mitigated by certain risk factors.

Now let’s change Earl’s word “morally” to “legally” – is it obvious that John is, or rather under ideal laws should be, legally obligated?

And now suppose there is a pro-lifer, PL. PL feels sincerely that a pregnant woman should be legally prevented from aborting, so long as the woman’s risk of grave loss of well-being appears small. PL feels this deeply, but let’s say that PL’s logical powers are not strong.

A pro-choicer, PC, asks PL: Should John be legally obligated to do everything in his power to keep the child alive?

PL: Maybe not.

PC: Isn’t requiring a pregnant woman to keep her child alive parallel to requiring John to keep the child alive?

PL: I guess so, I don’t know.

PC: Then maybe a pregnant woman shouldn’t be legally required to keep her child alive?

PL: No, I think she should.

PL’s “I guess so” betrays logical inconsistency: at the same time that PL guesses – within the limits of his/her logical abilities – that two situations are morally parallel, s/he holds differing intuitions about the respective moral principles that should apply and be translated into law.

But that doesn’t necessarily mean that either intuition – the intuition about legal obligation in pregnancy or the intuition about legal obligation in the “John situation” that at least seems analogous to pregnancy – is incorrect. Let’s assume they are both correct. If they are, PL’s ineptness at debate wouldn’t make either one incorrect.

PL may not be very smart, but then no human being’s logical power is infinite. It’s quite possible that there is some subtle disanalogy (failure of analogy) between the “John situation” and the pregnancy situation, such that PL’s intuitions about both situations are correct; yet even if Judith Thomson, Don Marquis and Aristotle were all combined into one, they might not be able to figure out what that disanalogy between the “John situation” and the pregnancy situation is.

It might also be that PL’s moral intuitions about many other situations are incorrect, yet his/her intuitions about the “John situation” and about pregnancy are correct.

It might be that all the logical power of the human race (which is pretty puny in absolute terms, after all) may never be able to figure out what that disanalogy is (most likely, there is a combination of disanalogies working in different directions to shift the intuitive balance one way or another). That inability would not mean that PL’s intuitions were incorrect. Indeed, PL’s “John” intuition and pregnancy intuition are both correct.

If all the logical power of the human race cannot figure out what the disanalogy is, then there is only one way to arrive at both correct intuitions – the direct intuitive way, not requiring logic – and there is no foolproof way to convince anyone who holds incorrect intuitions that PL’s intuitions are both correct, though in fact they are both correct.

I mentioned earlier, “Logic may lead us close to the door of intuition, with luck very close, but in order to pass through we have to leave logic behind.” Trying with his/her logic to compare the situation of pregnancy (in which PL feels that a pregnant woman should normally be obliged to accept the degree of risk necessary to “help” her unborn child), with the “John situation” above (in which PL feels that a hiker should not normally be obliged to take a risk to help a child), PL could not immediately find any morally relevant difference. The “John” analogy did not radically change PL’s intuition about pregnancy, but it may have nudged PL in the direction of a different intuition.

If two people have differing intuitions about situation A, but one of them posits a somewhat similar situation B and another somewhat similar situation C which elicit in him the same intuition he had about A, and the other person agrees with the first person’s intuition about B and C, then the logic of the similarities/parallels may lead the second person close to the door of the same intuition on A as the first person. But that logic cannot take the second person through the door into a pre-logical realm. And if there is no situation very similar to A, then such comparison of situations may not even lead that second person very close to that particular door.

A corollary to the above would be: Everyone in the world might be logically convinced of the validity of an intuition – say PL’s intuition, on which the principle “a pregnant woman should, in many cases, be legally prevented from aborting” is based – yet the intuition could nevertheless (due to the finite nature of our logical power) be incorrect.

I think it would be true to say that you could arrive at a correct moral principle through intuition alone, without logic, but you could not arrive at a correct moral principle through logic that is not based on intuition. To take Judith Thomson’s famous thought experiment as an example, what causes most people to say that the kidnapped person is not obliged to lend their body for the use of a severely ill violinist? It is not logic, but simply a direct moral intuition about that particular situation. We do not need to be told another story, a story about a trombone player, in order to have the intuition that we have about the violinist. This shows the primacy, in moral investigations, of direct intuition about a specific situation. We do not need to be told a story about a violinist in order to have a basic intuition about pregnancy.

Logic and analogies do seem to resonate somehow in our unconscious minds whence intuitions come, but by definition we do not experience what the unconscious is thinking. As PL’s example showed us, the unconscious may disagree with the best of a person’s conscious logic. It could even be that the unconscious is employing a superior logical power, but we don’t know.

In “De Facto Guardian and Abortion,” Steve Wagner, Timothy Brahm and the other authors find their pre-logical moral intuitions that someone should be legally obligated to feed a hungry child that is dependent on them to survive. They then proceed, in a section called “Making Sense of Our Intuitions,” to cogitate logically about the morally relevant factors and to develop the category of “de facto guardian” to characterize someone with this relationship with a hungry child [1].

While I agree with them on most details and am grateful for what they have done, I would like to explore the rationale for this section: If there were no plausible logical way to “make sense of their intuitions,” would that mean that the intuitions were wrong? If there were a way, but no logical power on earth could find that way, would that mean that the intuitions were wrong? If there were a way, but these particular individuals could not find the way, should they moderate the degree of their conviction about the matter? And is there ever really any need for intuition – could these authors, for instance, have come to the same moral principles through logic alone?

The opinion on this that I expressed above is “you could arrive at a correct moral principle through intuition alone, without logic, but you could not arrive at a correct moral principle through logic that is not based on intuition.” Logic can nudge me toward a certain moral intuition, correct or incorrect, but that moral intuition I have found is pre-logical and pre-verbal. It cannot be said that I have simply come to a logical conclusion.

The Practical Implications

Now let us see whether all my academic moral philosophy has any practical importance, particularly for the abortion debate. The origins of correct moral principles, or (if the idea of moral absolutes is not accepted) at least valuable moral principles, and the role of logic in the development of such principles, are certainly at the foundation of moral philosophy. But apart from academic moral philosophy, do the views I have stated, even if they are correct, matter?

Moral principles certainly have practical implications – in the case of the abortion issue, such principles, as translated into law or even simply as influential social norms, determine every day whether unborn babies will live and whether their mothers will have to accept unwished-for changes in their lives. So moral principles have practical implications, and I think that my views above have some practical implications as well that will help us determine the best moral principles.

Some of the practical implications are as follows:

1. It is well-known that people tailor their logic to their intuitions to a large extent, and I think that much of this occurs unconsciously. If people begin to think that intuitions are not always disrespectable and logic (on moral issues) is not always sacred, they will become more motivated to look within at their intuitions and to try to grasp what those intuitions are and how those intuitions interact with their more conscious mental processes. The workings of their minds will become clearer to them; they will be following the adage “Know thyself.”

We are all out advocating policies that mean life or death for others, without completely knowing why we are doing so. I don’t think it is possible to know completely, but it is possible to know better and knowing may catalyze change in the right direction.

2. If we become aware that our exploration of thought experiments and the like is an exercise in experimenting with logic to help us find a moral intuition already existing in our unconscious – rather than an exercise in deriving a moral intuition or moral principle through logic itself – this also will motivate us to look within at our intuitions. That is, we will assign a higher priority than before to the kind of contemplative approach that can move us most directly toward the deep-seated intuition.

3. If the representatives of both sides on any issue – say a pro-lifer and a pro-choicer on the abortion issue – can agree that the debate is really a matter of one intuition versus another, I think that this will work in two ways. On the one hand, each of the two will admit to himself that his intuition comes out of his unconscious in ways he cannot understand, and this should produce greater humility about those intuitions – not a direct weakening of the two people’s intuitions in the intuition area of their brains/minds, but rather greater humility in the pride/humility area of their brains/minds. This will reduce the ego clutter and make changes of intuition easier. Yet on the other hand, the debaters will develop greater trust in their intuitions relative to their logic, recognizing that, for better or worse, there cannot be any moral truth unsupported by intuition.

4. I think that people’s egos are more wrapped up with their logical powers than with their intuitions. If people come to realize that that which involves their egos – logic – will not ultimately prove anything or bring a discussion about a moral issue to any final conclusion, then each party in a debate might become emotionally less defensive about their logical powers, leading them to relax their egos. This also would very much reduce the clutter in their thinking processes.

5. I referred above to looking “within at their intuitions.” I would like to see a discussion between the parties on both sides of any issue – say between a pro-choicer and a pro-lifer – that begins with each party examining their own intuitions and related feelings (feelings being not exactly the same as intuitions). How does the thought of an unborn child dying in an abortion make me feel? Do I feel the pain in my body? If not, where does that feeling come from? Is it necessarily valid? How do I know it’s valid?

Then each party would try to describe those intuitions and physical-emotional feelings to the other party. A pro-lifer might say: “It pains me here [pointing probably to the chest region] to think of my innocent little unborn sister or brother, just beginning their life, being ripped apart.” A pro-choicer might say on the other hand: “It pains me here [also pointing to somewhere in the chest region] to think of my pregnant sister, already under such a burden, being told what she can or cannot do within her body.” (In this scenario, they are using “sisters” and “brothers” in a spiritual or humanistic sense.)

(“Appeals to emotion” have a bad name. Appeals to emotion can be manipulative, but I think that an expression of one’s genuine emotion is likely to better represent one’s moral intuition than an attempt to represent it logically.)

Then the two proceed to discuss the violinist, the Cabin in the Blizzard, the “John” thought experiment, and so on, at each point reporting “This makes me feel such-and-such deep inside.” If the two wish, they can logically examine the relative extents of all the analogies and disanalogies of the thought experiments as well.

At the end, each will again examine and report their direct intuition about pregnancy itself – not about any analogy with pregnancy, but about pregnancy itself. Perhaps their intuition will have changed, or will be on a slow road toward change.

Through a better understanding of the roles of intuition and logic in moral investigations, I think that those participating in any discussion will be able more quickly to identify the differences in intuition that separate them and think also that each person will better realize that she cannot fully explain the origins of her own intuitions, even to herself.

The Evolution of Moral Intuitions

In the build-up to the abolition of slavery in the United States, many people intuited that slavery was wrong; but the fact that slavery was ultimately abolished doesn’t mean that it was ever proved logically to be wrong. The abolitionist intuition was not proven; it prevailed. There is now a consensus, which I agree with, that slavery is wrong – that what prevailed, in other words, was the correct intuition – but even today, if someone were to advance a logical argument saying that slavery is right, that argument could not be conclusively defeated on its own terms. What our moral intuitions regarding slavery have undergone has been a process of evolution, and our moral intuitions regarding abortion will undergo the same. The question of the morality of slavery is ultimately intractable to a logical approach and so are questions of the morality of abortion and of abortion law.

Though I don’t know if he would agree with me about the limited role of logic, I will quote Paul Bloom again: “Good moral ideas can spread through the world in much the same way that good scientific ideas can, and once they are established, people marvel that they could ever have thought differently.”

Sam Harris’ The Moral Landscape presents an argument – which I am open to, with a few exceptions – that the neuroscience of the future could measure the well-being of a population, and see how that well-being responds to variations in the moral principles of the population, accurately enough to determine scientifically which moral principles are best. This all presupposes a consequentialist definition of “best,” which I’m open to. In any case, the reality of this approach lies too far in the future to be useful to us now. For now we can only try to find our best moral intuitions.

Someone on the pro-choice side will likely say that my arguments, coming as they do from a pro-lifer, confess to a weakness of logic on the pro-life side. Fine. Such an assertion would not diminish the power of any good logic or good intuitions on any side.

I would like to thank Jake Earl, who created the “John” thought experiment. The probing questions of various people, but most definitively of Earl, helped me to better think things through.

Acyutananda has a pro-life blog at

Work Cited:

[1] Stephen Wagner, for the Justice for All Philosophy Team, “De Facto Guardian and Abortion,” Life Report, accessed April 13, 2015,


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