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Friday, September 10, 2010

Why Hume's Guillotine Fails with regard to Ethical Intuitionism

Some theists have argued that Hume's Guillotine effectively eliminates the possiblity of there being  moral facts given a naturalistic world-view. What is Hume's Guillotine?
Hume's Guillotine, also known as the "is-ought problem" or Hume's law is a criticism of writings by ethicists who make normative claims (about what ought to be) based on positive premises (about what is). The problem was articulated by David Hume in his most important philosophical work, A Treatise of Human Nature (Book III, §I).

Hume argued that one cannot make a normative claim based on facts about the world, implying that normative claims cannot be the conclusions of reason.

The term "Hume's Guillotine" is meant to describe the severance of "is" statements from "ought" statements, which similarly, and colourfully, illustrates the resulting removal of the head from many ethical arguments.

One may consider the following moral argument as an example of an is-ought problem:

1.Sam is stealing money from work.
2.Losing money by theft causes harm to Sam's employers.
3.(One ought to not cause harm to his employers.)
4.Therefore, Sam ought to stop stealing money from work.

Premises 1 and 2 are "is" statements, describing facts of what is happening. Premise 3 and Conclusion 4 are "ought" statements, that describes how things should be happening. But what is the source of this knowledge? This argument appears to be valid if the premises are true, but unless we can logically support Premise 3, it is not sound. What can possibly give us rational knowledge that things ought to be different than the way things are?

Why doesn't Hume's Guillotine effectively decapitate ethical intuitionism? Simply because ethical intuitionism holds that there are certain moral facts that are self-evident, and are not based on inference or conscious reasoning.  One definition of Ethical Intuitionism is a view in moral epistemology according to which some moral truths can be known without inference ("Ethical Intuitionism").  Hume is arguing that one cannot move from a descriptive fact (how something is) to a prescriptive fact (how something ought to be) by means of inference or deduction. However, that is not what ethical intuitionists do. Listen to Brian Zamulinski:

Inference is an intellectual movement from proposition to proposition. Apprehension is the acquisition of a belief in response to a state of affairs. Our ability to apprehend states of affairs is not fundamentally an ability to make inferences, no matter what sorts of inferences. It is an ability to see that such and such is the case. With evolutionary intuitionism, we intuitively apprehend the fact, say, that torture is wrong. We do not infer the belief that torture is wrong from other propositions. Since inference is not involved, the impossibility of inferring an "ought" from an "is" is not relevant. The is/ought gap is of no significance whatsoever for evolutionary intuitionism (Evolutionary Intuitionism: A Theory of the Origin and Nature of Moral Facts [2007], p. 112).


  1. Very timely, in light of Sam Harris' forthcoming book. To my understand, he argues precisely that we can derive an "ought" from an "is", so long as we acknowledge basic facts about the human condition.

  2. Ken,

    The problem I see with ethical intuitionism is that it's akin the the line of reasoning used by Plantinga and the apologetic presuppositionalists. They argue that belief in God is properly basic and is merely "apprehended," much like you are arguing that morality is merely "apprehended."


  3. I think that Plantiga's point, the some beliefs are properly basic, is good. But these beliefs can be defeated by empirical evidence to the contrary.

    A belief in God might be properly basic, but not a belief that the Bible is accurate. The former can be unfalsifiable, akin to believing that life has meaning, the latter is a statement about history and science.

    So I think Ken's "intuitions" are like proper first principles. They are general statements - wrong to hurt, good to help. We have to start somewhere.

  4. Louis,

    Yes it is similar in that both hold to a foundationalist epistemology. However, Plantinga admits that the belief in God while properly basic is defeasible. He just doesn't think it has been defeated. Not all of our intuitions, including ethical intuitions, are accurate. They can be defeated. I tend to think there are just a few very basic moral intuitions and these serve as the basis for further moral reasoning.

  5. Ken,

    I'm afraid that this defense of intuitionism trades on an equivocation over the meaning of inference. The ability to directly intuit certain truths about the way things are does not imply that those truths do not have grounds which could be reconstructed via an inferential argument. When I see and recognize a tree I do not construct an inferential argument from certain features of my perceptual experience to the existence of the tree, but those features do nonetheless ground my perception, and if those features do not track the features of the tree my perception is illusory.

    I think it would be better to say that intuitionists do not think epistemic access to certain inferences is necessary in order to have knowledge. That is, intuitionism is committed more or less to externalism in epistemology: I can perceive or know something is true without being able to give an inferential argument for its truth. But it remains the case that unless perception tracks real features of the world, it is illusory, whether that perception is direct or not.

    The theistic argument is that a naturalistic world lacks those features (such as moral facts) which ground moral intuitions, not that moral intuitions are without force unless based upon conscious reasoning. It is an ontological, not an epistemological argument.

  6. So Ken,
    "The Grand Design"...

    So design comes from non-design?

    The universe can 'create' us, and we can understand the universe, but the universe cannot understand us?

    The effect is greater than the cause?