From: "Hill, David"Date: Wed Feb 20, 2002 4:31pm Subject: RE: [evol-psych] "ought" can be plausibly derived from an "is"? Irwin Silverman wrote: I am not a professional philosopher so forgive me if this is naive, but I see your example above as an apt demonstration of the dichotomy between "is" and "ought" Your knife "is" dull - that is a fact. But whether you "ought" to sharpen it or not is a value judgement, depending potentially on many things - e.g. how you plan to use it (are you a serial killer?) - whether you have to forego more critical purchases to buy a knife sharpener, etc. I don't mean to offend, but these protracted discussions of the obvious remind me of Alexander Pope - "A man of business may talk of philosophy; a man who has none may practice it." _______ Reply: This simply ignores the concession plainly present in my posting. That the one statement does not entail the other as a logically valid consequence, sans supporting premises, is obvious. In any case, the relevant point is that statements about better and worse behavior may follow from premises available to us all, together with results that might possibly be obtained from EP. By the way, why do people typically say (without argument) that "ought" claims are value judgments? To say that X ought to do Y is not, prima facie, to make any value judgment at all. It is not, for example, to say that doing Y is better than not doing Y, or that it would be good for X to do Y. Indeed, it is perfectly consistent -- though odd -- to say "Y is a very bad thing and I rather hope you won't do it, but nonetheless you have an obligation to do it and ought to do it." Between "ought" claims and ordinary value judgments there is at least as much of a logical gap as any between is's and oughts. David Hill writes: There is an interesting assumption that runs through this and similar arguments for Hume's semantic dualism. The assumption is that if we can't get entailments from descriptions, what good is the evidence anyway? To which one ought to respond that descriptions are not typically more certain than normative claims, and thus nothing is to be gained by restricting one's evidence set to claims that are rigidly descriptive. An outstanding moral philosopher once put it this way. "If these lovers of tidy logical dichotomies don't want to call the derivation "implication," then I give them the word. Call it "shimplication." Call it whatever you wish. The question is whether the sustaining argument is sound, not whether it fits neatly into Hume's impoverished ontology." If someone could derive significant moral conclusions from factual descriptions, plus an appropriate functional analysis of a Darwinian sort, plus a few unchallenged axioms, that would be worth doing, however you characterize the several sorts of premises involved.