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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