The moral-facts-denier are welcome to counter the argument below;
- How to Derive "Ought" From "Is"
John R. Searle
The Philosophical Review
Vol. 73, No. 1 (Jan., 1964), pp. 43-58
As a convenience I will post a John Searle' Summary from page 52-58,
Section III of John Searle's Article, Verbatim below;
So far I have presented a counterexample to the thesis that one cannot derive an "ought" from an "is" and considered three possible objections to it.
Even supposing what I have said so far is true, still one feels a certain uneasiness.
One feels there must be some trick involved somewhere.
We might state our uneasiness thus: How can my granting a mere fact about a man, such as the fact that he uttered certain words or that he made a promise, commit me to the view that he ought to do something?
I now want briefly to discuss what broader philosophic significance my attempted derivation may have, in such a way as to give us the outlines of an answer to this question.
I shall begin by discussing the grounds for supposing that it cannot be answered at all.
The inclination to accept a rigid distinction between "is" and "ought," between descriptive and evaluative, rests on a certain picture of the way words relate to the world.
It is a very attractive picture, so attractive (to me at least) that it is not entirely clear to what extent the mere presentation of counterexamples can challenge it.
What is needed is an explanation of how and why this classical empiricist picture fails to deal with such counterexamples.
[The Classical Empiricist Picture is as Follows;]
Briefly, the picture is constructed something like this:
- first we present examples of so-called descriptive statements ("my car goes eighty miles an hour," "Jones is six feet tall," "Smith has brown hair"),
and we contrast them with so called evaluative statements ("my car is a good car," "Jones ought to pay Smith five dollars," "Smith is a nasty man").
We articulate the difference by pointing out that for the descriptive statements the question of truth or falsity is objectively decidable, because to know the meaning of the descriptive expressions is to know under what objectively ascertainable conditions the statements which contain them are true or false.
But in the case of evaluative statements the situation is quite different.
To know the meaning of the evaluative expressions is not by itself sufficient for knowing under what conditions the statements containing them are true or false, because the meaning of the expressions is such that the statements are not capable of objective or factual truth or falsity at all.
Any justification a speaker can give of one of his evaluative statements essentially involves some appeal to attitudes he holds, to criteria of assessment he has adopted, or to moral principles by which he has chosen to live and judge other people.
Descriptive statements are thus objective, evaluative statements subjective, and the difference is a consequence of the different sorts of terms employed.
The underlying reason for these differences is that evaluative statements perform a completely different job from descriptive statements.
Their [evaluative statement’s] job is not to describe any features of the world but to express the speaker's emotions, to express his attitudes, to praise or condemn, to laud or insult, to commend, to recommend, to advise, and so forth.
Once we see the different jobs the two perform, we see that there must be a logical gulf between them.
Evaluative statements must be different from descriptive statements in order to do their job, for if they were objective they could no longer function to evaluate.
Put metaphysically, values cannot lie in the world, for if they did they would cease to be values and would just be another part of the world.
Put in the formal mode, one cannot define an evaluative word in terms of descriptive words, for if one did, one would no longer be able to use the evaluative word to commend, but only to describe.