Hume’s empiricism and metaethics

1. Hume’s empiricism and metaethics Michael Lacewing

2. Hume’s fork • We can only have knowledge of • Relations of ideas • Matters of fact • Relations of ideas are a priori and analytic • Matters of fact are a posteriori and synthetic

3. The options • For any field of knowledge, Hume has three options: • to say that any knowledge we do have is based on experience • to say that any knowledge we have is trivial (analytic, true by definition) • to deny that we have any knowledge in that area.

4. Is morality about relations of ideas? • Can any relation of ideas be distinctive of morality (i.e. apply only in moral judgments)? • E.g. Killing: not with plants • Wilful killing: “a will does not give rise to any different relations, but is only the cause from which the action is deriv’d” (Treatise, 519) • Relations of ideas work with deductions and proof – doesn’t seem right model for moral reasoning • Kant?

5. Is morality about matters of fact? • Which facts, e.g. in wilful murder, are moral facts? • “you will find only certain passions, motives, volitions, and thoughts… The vice entirely escapes you, as long as you consider the object. You never can find it, till you turn your reflection into your own breast, and find a sentiment of disapprobation, which arises in you, towards this action. Here is a matter of fact; but ‘tis the object of feeling, not of reason. It lies in yourself, not in the object.” (520)

6. Drawing moral inferences • “In the disquisitions of the understanding, from known circumstances and relations, we infer some new and unknown. In moral decisions, all the circumstances and relations must be previously known; and the mind, from contemplation of the whole, feels some new impression of affection or disgust, esteem or contempt, approbation or blame. Hence the great difference between a mistake of fact and one of right” (Enquiry concerning the Principles of Morals, 290)

7. The is-ought gap • Matters of fact do not entail moral judgments: • ‘this ought…expresses some new relation [of which it] seems altogether inconceivable, how this new relation can be a deduction from others, which are entirely different from it’. (Treatise, 521) • To move from ‘is’ to ‘ought’ is only possible through the interposition of a feeling or preference. • Explanation: morality is not a matter of fact, but of attitude/feeling.

8. Moral knowledge? • Moral judgments don’t express truth claims. • Sentences such as ‘abortion is wrong’ don’t state propositions (which can be true or false), they express attitudes. • So, there can be no moral knowledge because there are no moral facts that we can know or not know.

9. Universal morality • Hume is not a subjectivist. • The feeling/attitude morality expresses is the same for all of us, because of human nature. • Morality rests on our responses of sympathy. • This can’t be ‘right’ or ‘wrong’, but we tend to react the same, and reasoning can clarify our feelings.

10. Moral reasoning • But when justifying a moral claim… • E.g. Eating meat is wrong • …we appeal to natural facts • E.g. Animals suffer. • Moral reason: a reason for someone to do something • E.g. That animals suffer is a reason for you to not eat meat. • That some fact is a moral reason is a relational property.

11. Moral truth • Whether some fact is a reason is objectively true or false. • Epistemic reasons: Radiometric decay indicates that the some dinosaur bones are 65 million years old. This is (objectively) a reason to believe that dinosaurs lived on Earth 65 million years ago. • Facts about reasons are normative facts.

12. Moral truth • To say that something is wrong is to say that the moral reasons against doing it are stronger than any moral reason in favour of doing it. • The judgment, ‘x is wrong’, is objectively true or false. • Hume is right that natural facts do not establish moral truths. We must also consider the normative facts.

13. Are moral reasons objective? • But are there truths about moral reasons, independent of people? • Hume would argue that moral reasons are relative to individuals – whether the fact that animals suffer is a reason for me not to eat meat depends on whether I care • Because sympathy is universal, then we all care about many similar things