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Moral Skepticism

Original text: Moral Skepticism

Summarized: 4 minute read

1. Varieties of Moral Skepticism

Moral skeptics raise doubts about common beliefs. They might doubt categorical or absolute moral beliefs without doubting weaker kinds of moral beliefs, or they might raise doubts about moral knowledge or justified moral belief.

Moral skepticism comes in two varieties, Pyrrhonian skepticism about moral knowledge and dogmatic skepticism about justified moral belief. Pyrrhonian skeptics do not make any claims about the actuality or possibility of moral knowledge or justified moral belief.

Skepticism about moral knowledge is implied by skepticism about justified moral belief, but skepticism about moral truth is not implied by skepticism about moral truth-aptness, truth-value, or falsehood.

Many moral theorists conclude that moral assertions express not only emotions or prescriptions but also beliefs. However, this non-skeptical linguistic analysis still does not show that such moral claims can be true, since assertions can express beliefs that are false or neither true nor false.

Skepticism about moral reality is a reason for skepticism about moral falsehood, or skepticism about moral truth-value. Opponents of such error theories often object that some moral beliefs must be true because some moral beliefs deny the truth of other moral beliefs.

A non-epistemological form of moral skepticism answers the question “Why be moral?” by denying various universal claims, including the claims that there is always some kind of reason to be moral, that there is always a distinctively moral reason to be moral, and that there is always enough reason to be moral.

Practical moral skepticism denies a role to reasons in morality, whereas epistemological moral skepticism denies that there is ever an adequate reason for moral belief. Consequently, practical moral skepticism does not imply epistemological moral skepticism.

There are several kinds of moral skepticism, including dogmatic skepticism about justified moral belief, Pyrrhonian skepticism about moral knowledge, and practical moral skepticism.

2. A Presumption Against Moral Skepticism?

Skeptics about justified moral belief can act well and be nice people. They need not be any less motivated to be moral than non-skeptics, nor do they need to have any less reason to be moral than non-skeptics.

Critics still argue that moral skepticism conflicts with common sense, and that it is therefore unjustified. Furthermore, dogmatic moral skepticism is a universal and abstruse claim, and thus it seems that one should not make such a claim without some positive argument.

Moral skeptics sometimes try to shift the burden of proof from themselves to their opponents, but dogmatic moral skepticism and Pyrrhonian moral skepticism are different. Dogmatic moral skeptics make a universal claim that conflicts with common sense, while Pyrrhonian moral skepticism does not.

3. Arguments for Moral Skepticism

Moral skeptics offer a variety of arguments for their position, including those that focus on justified moral belief, but which could also be applied to moral knowledge.

3.1 Moral Disagreements

A common argument for moral skepticism is that smart and well-meaning people disagree about the moral permissibility of abortion, affirmative action, capital punishment, active euthanasia, nuclear deterrence, welfare reform, civil rights, and so on. However, this does not exclude the possibility of agreement on other moral beliefs.

3.2 Moral Explanations

Some philosophers argue that moral truths are never necessary for the best explanation of any non-moral fact, but this argument can be countered by arguing that sometimes a moral truth is necessary for the best explanation of a non-moral fact.

Some moral skeptics argue that moral beliefs can be explained by evolutionary biology perhaps with help from psychology, sociology, or culture without appeal to any moral fact or truth. However, it is not clear whether or not non-moral explanations really do work as well as moral explanations in all cases.

3.3 A Regress

Cannot be easily summarized – click here for a full explanation 

3.4 Skeptical Hypotheses

The final kind of argument derives from René Descartes (1641). It states that if there is any contrary hypothesis that cannot be ruled out, then I am not justified in believing that what I see is a lake.

The Cartesian hypothesis is that there is a deceiving demon who deceives me in all of my beliefs about the external world, while also ensuring that my beliefs are completely coherent. This hypothesis is also contrary to my beliefs about the lake.

Moral nihilism is a thesis that there is nothing morally wrong, and that people hold moral beliefs that are false. Moral skeptics can argue that the definition of moral nihilism forestalls any refutation, and that the explanation of moral beliefs predicts that we would hold these beliefs.

According to the general principle above, one must be able to rule out moral nihilism in order to be justified in believing that torturing babies just for fun is morally wrong. Moral skeptics conclude that this moral belief is not justified.

The argument can be generalized to cover any moral belief, and moral skeptics conclude that no moral belief is justified.

There are two main responses to such skeptical hypothesis arguments: some anti-skeptics deny (1) and claim that skeptical hypotheses can be ruled out somehow. However, moral nihilism does seem consistent and meaningful, according to all plausible theories of moral language.

Alternative theorists claim that only relevant hypotheses need to be ruled out, and therefore a belief that it is morally wrong to torture babies just for fun can be justified.

For this response to have force, opponents of moral skepticism need to say why moral nihilism is irrelevant. If moral nihilism is relevant, and if closure holds for all or at least relevant alternatives, then moral skepticism seems to follow.

3.5 Relations Among the Arguments

These arguments for moral skepticism differ in many ways, but they seem mutually supportive. If moral intuitionism, coherentism, naturalism, or normativism works to justify some moral beliefs and/or to rule out moral nihilism, then this will undermine the crucial premises in the arguments for moral skepticism.

4. Pyrrhonian Moral Skepticism

A moral belief can be justified by counterexamples to another moral belief, but not by counterexamples to another moral belief if the alternative is not subject to the same counterexamples.

Moral nihilism is not taken seriously in ordinary discussions, so the modest contrast class does not include moral nihilism. Therefore, anyone who can rule out all other members of the modest contrast class but cannot rule out moral nihilism is justified in believing the moral claim.

Problems arise when contexts cross, and it is hard to say which context is relevant for assessing whether a believer really is justified (without qualification).

Some Pyrrhonian moral skeptics deny that any contrast class is ever really relevant, while others suspend belief about whether any contrast class is ever really relevant or not, and still talk about whether someone is justified in believing a moral claim out of a specified contrast class.

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