How much should we trust our moral intuitions? Is the task of ethics to describe those intuitions, or to change them?

Grant Babcock
Philosophy & Policy Editor

Grant Babcock is the Philosophy and Policy Editor of Lib​er​tar​i​an​ism​.org and a scholar of political philosophy. He is especially interested in nonviolent action, epistemology of the social sciences, social contract theories and criticisms thereof, and finding libertarian‐​compatible responses to cultural problems.

A central theme in Hayek’s writing on social norms is his argument against “constructivism,” or trying to build ethics from scratch using reason. A lot of other libertarian thinkers share Hayek’s suspicion.

Today, I’m going to argue that there are major problems with many of the most prominent alternatives to constructivism: Specifically, these alternatives put more weight on our ethical intuitions than they will bear.

One well‐​known alternative, which John Rawls called “reflective equilibrium,” is an iterative process where we start with a moral theory and moral beliefs and reflect on how well they match and how they could be made to match better. We then tweak either the theory or our moral beliefs and repeat the process until we have reconciled our theory with our beliefs: that is, until we have reached equilibrium.

Another is Matt Zwolinski’s argument for libertarianism from a position called “moral pluralism.” Under moral pluralism, we have a set of prima facie plausible (i.e. plausible according to one’s initial impression) ethical guidelines which we apply to moral cases. We then rely on our judgement—that is, our moral sense—to resolve any contradictions in applying the guidelines. Michael Huemer’s argument for libertarianism, laid out in his 2013 book The Problem of Political Authority, rests squarely on ethical intuitions; in fact, intuitions are so central for Huemer that he calls himself an “intuitionist.”

Arguments of this type are mistaken about what determines the truth of moral propositions. Specifically, they misunderstand the relationship between ethical theories and our intuitions about ethical principles and cases.

Many people believe that it counts in favor of an ethical theory if its logical consequences line up with our intuitions about moral cases. The idea here, sometimes explicitly stated, sometimes only implied, is that an important causal reason for certain intuitions is that those intuitions are true. A simple example would be the position that our conscience gives us direct access to moral facts in a manner analogous to how our eyes give us access to facts about the wavelength and intensity of light. On views of this type there is a causal line from moral fact X being true to my believing X; it’s not merely a correlation or a coincidence.

Here’s a potential problem with such views: our intuitions about moral cases could be mostly hogwash. Indeed, we have good reasons to be very suspicious of our intuitions about moral cases, at least at first. That’s because many of those intuitions didn’t develop in response to moral truth, but rather in response to evolutionary pressure and social conditioning.

Philosopher Peter Singer does a good job of explaining the ways biological evolution seems to influence our moral intuitions in his 2005 paper “Ethics and Intuitions.” Singer is well‐​known for holding views about ethics that run contrary to our intuitions, so he needs an account of why we shouldn’t trust those intuitions. His answer is that the correct explanation for why we hold certain intuitions is not that those intuitions are true, but that those intuitions are evolutionarily advantageous.

For example, most people think they have a greater responsibility to look out for their family members than for strangers. In “Ethics and Intuitions,” Singer points out that evolution would select for this instinct. A gene that makes you look out for your family is a gene that makes you look out for other people carrying that same gene, so we would expect evolution to select for it. Singer says that our instinct that we have a greater duty to help our families is a product of biological evolution. In a different paper, Singer argues that contrary to this instinct, morality requires that we give roughly equal moral weight to the welfare of our children and the welfare of a starving refugee we will never meet.

One might still say that Singer is wrong about what we owe our families, and Singer hasn’t necessarily precluded all types of objections. What he has shown, I think pretty convincingly, is that a viable counter‐​argument to his claim about family duty can’t rely on intuition. That’s because our intuitions about the duties we have to our families are very likely attributable to genetics.

This doesn’t mean that our intuitions are always wrong. Sometimes genetics might favor dispositions that are justifiable, but even in those cases, the cause of our having that disposition isn’t its correctness. We need to be careful not to unintentionally conflate moral truth with survival advantage.

Although I agree with Singer that some of our moral intuitions are best explained by evolution, I don’t think that all of our intuitions are genetically inherited. Friedrich Hayek identifies another potential cause of our having the moral intuitions that we do. In Law, Legislation, and Liberty, Hayek hypothesizes: “The brain is an organ enabling us to absorb, but not to design culture.

Focusing on the first part of that quote, we see that on Hayek’s account humans are able to internalize and follow rules of conduct. This means that, in addition to having moral instincts that are a product of evolution (as Singer argued), human beings will have moral instincts that are learned. Furthermore, we can choose to reject and abandon these learned norms of conduct. Hayek says that a selection process operates on the laws and norms of society that is similar to the selection process operating on genes in biological evolution. What sort of norms will survive? Well, just the sort enabling the people holding those norms to spread them and encourage other people to adopt them of their own accord.

Moreover, says Hayek, biological evolution and cultural evolution took place and are taking place concurrently. Our brains are conducive to adopting norms from our social context, he claims, because our species evolved in a social context.

But can we attach any moral weight to the sort of norms and instincts that we hold because of evolutionary pressures on our genome or on our culture? I’m going to hold off on Hayek’s answer for today. Singer’s answer in “Ethics and Intuitions” is a clear “no:”

[A] normative moral theory is not an attempt to answer the question “Why do we think as we do about moral questions?” Even without an evolutionary understanding of ethics, it is obvious that the question “Why do we think as we do about moral questions?” may require a historical, rather than a philosophical, investigation….A normative moral theory is an attempt to answer the question “What ought we to do?” It is perfectly possible to answer this question by saying: “Ignore all our ordinary moral judgements, and do what will produce the best consequences.” Of course, one would need to give some kind of argument for this answer.

What this means is that we shouldn’t judge a moral theory based on how well it predicts people’s actual moral instincts, says Singer:

There is little point in constructing a moral theory designed to match considered moral judgments that themselves stem from our evolved responses to the situations in which we and our ancestors lived during the period of our evolution as social mammals, primates, and finally, human beings.

To carry Singer’s argument further, the idea that moral theory should “predict” people’s moral instincts is, in fact, precisely backwards. If a prospective moral theory doesn’t have some consequences which (at least at first) produce negative gut feelings, we should take that as evidence that our moral theory is likely to be wrong in ways that ratify and support unjustifiable aspects of the status quo. We cannot presume a causal connection between our feelings of guilt, disgust, outrage, and so on, and moral truth; we have to offer arguments that hold up even if those reactions turn out to have some other cause.

If we can’t trust our instincts to lead us to moral truth, one response might be moral skepticism—the position that there simply is no such thing as moral truth. But Singer says there’s an alternative:

[W]e might attempt the ambitious task of separating those moral judgments that we owe to our evolutionary and cultural history, from those that have a rational basis. This is a large and difficult task. Even to specify in what sense a moral judgment can have a rational basis is not easy. Nevertheless, it seems to me worth attempting, for it is the only way to avoid moral skepticism.

Near the beginning of this essay, I remarked that Hayek doesn’t much care for constructivism, or, as he sometimes calls it, “constructivist rationalism.” Yet, I think that an appropriately humble type of constructivist rationalism is our best chance to avoid skepticism about ethics, and thus skepticism about any political theory based on a moral philosophy (libertarianism included). Constructivist rationalism is the idea that we could discover ethical truths about the world by constructing an ethical theory using reason, analogously to how we can discover truths about the world by constructing a theory of mathematics using reason. Mathematical facts don’t depend on any observations on our part, yet they nevertheless give us access to truth that exists “out there.” I think ethical facts, if there are any, work like mathematical facts.

Hayek is often read as proving that a rationalist ethics of the type I just described is impossible. Next time, we’ll explore why I don’t think that’s the case.