[U03] Facts and moral values

The following are descriptive statements. they purport to describe facts :

  • This is a sharp knife.
  • Sam lied.
  • Mozart and Beethoven are composers.
  • Tom is dying painfully.
  • Ann believes that freedom of speech is important.

These, however, are statements about values :

  • This knife is a very useful kitchen tool.
  • It was wrong for Sam to lie.
  • Mozart is a greater composer than Beethoven.
  • It is better for Tom to die than to be alive.
  • Freedom of speech should be protected.

Philosophers usually distinguish between two kinds of values : instrumental values and intrinsic values. Instrumental values are sometimes also called "extrinsic values". Something is supposed to have instrumental value when it is not valued for its own sake, but because it contributes to some further purpose, or because it helps bring about something else of value. So a particular kitchen knife might be said to be very valuable in this instrumental sense - it is valued not for its own sake but because it can be used to satisfy certain culinary purposes that we treasure.

For further discussion on the distinction between instrumental and intrinsic values, you can read these two articles :

§1. Morality is normative and not purely descriptive

Here are some examples of moral claims :

  • There is nothing wrong with torture.
  • A democratic society should not enact unjust laws.
  • Abortion is permissible under certain situations.
  • We should not discriminate against homosexuals.
  • It was wrong for the police to play music to drown out the protest.

When we think about values, very often we are thinking about morality. What is distinctive about moral claims is that they are normative and not purely descriptive. They talk about right or wrong actions, what should or should not happen. However, although a moral claim is not purely descriptive, it can include some descriptive elements. For example, the last moral claim above implies the factual claim that the police did play music to drown out a protest. This is the descriptive element, and the normative component lies in the additional value judgement on what has been done.

Notice also that descriptive claims about moral beliefs in themselves are not normative. A few years back a survey in Hong Kong drew the conclusion that many young people think there is nothing wrong with corruption. This conclusion is a statement about the a moral belief shared by many young people. But the conclusion is a purely descriptive statement that does not evaluate the shared belief.

§2. The fact-value gap

Corresponding to the normative vs. descriptive distinction is the "is-ought" gap. What this means is that what is the case need not be what should be the case. Just because something is a matter of fact, it does not follow that it is something that is right, something that ought to happen. More precisely, it is a mistake to infer any moral claim purely on the basis of certain descriptive claims.1 Because this mistake is not uncommon, there is actually a name for it. It is called the naturalistic fallacy. Here are some examples :

  • There is nothing wrong being selfish. Everybody is selfish.
  • Homosexuality (or cloning, etc.) is wrong because it is unnatural.
  • Woman should stay at home and look after children because this is the tradition.
  • Animals eat each other in the wild. So we can eat them too.
  • In nature, only the fittest survive. Simiarly, in human society only the strongest will survive and this is the way it should be.

Many things can be said in response to these arguments. Just because many people are selfish does not mean that they are right. Many people used to think that slavery is acceptable, but we now think they were wrong. Plenty of things that are unnatural are not regarded as wrong, such as contraception or cosmetic surgery. Animals might eat their young or their old, but it does not mean that we should do the same to each other. Finally, some people end up in unfortunate circumstances through no fault of their own. Animals might not care about this, but it does not follow that human beings should act the way many animals do. In all these cases, we note that there are missing gaps in the original arguments : you need to assume that unnatural things are wrong, or that certain things which occur in nature or are widely accepted are morally correct. The purely factual premises are not sufficient to establish the normative conclusions, these additional bridging assumptions are needed.

This is not to say that facts are not needed to draw conclusions about right or wrong. To show that someone should be convicted of murder, you need to at least show that the accused did cause the death of the victim. But causing the death of a victim in itself does not show that something wrong has been done. Similarly, empirical facts relating to the effect of alcohol are needed in order to support the prohibition of drink driving. For example, you might introduce a version of the "harm principle", which says that something should be prohibited when it is likely to cause harm to innocent people. Harming innocent people is very likley if we allow driving under the influence of alcohol, so according to the principle it should be prohibited. In general then, if you want to argue that something is right or wrong, you need not just descriptive statements about facts but also additional moral principles.


1. For purported exceptions, see the discussion of Prior and Geach in Karmo (1988) "Some Valid (but no sound) Arguments Trivially Span the 'Is'-'Ought' Gap" in Mind Vol. XCVII, pp.252-257.

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