## Friday, March 28, 2014

### Another quick argument for the possibility of incommensurability

Suppose Curley is deciding whether to accept a \$1,000,000 bribe and lose his soul, or remain honest. It seems quite possible to have situations like this where neither option is preferable to Curley. Of course, prima facie that need not be a case of incommensurability--it might be a case of equal preference. But we cannot say that all similar cases like this are cases of equal preference. For in most cases like this, Curley also wouldn't have a preference between a \$1,010,000 bribe and honesty. If that too has to be a case of equal preference rather than incommensurability, then by the transitivity of equal preference, we would have to say in such cases that Curley has equal preference as to a \$1,000,000 bribe and a \$1,010,000 bribe. But of course that's false: in most cases like this, he prefers the larger bribe.

Brian Cutter said...

Neat argument. Here's a possible response on behalf of the no-incommensurability position, though: Accepting \$1,000,000 and remaining honest stand in a relation we might call *indiscriminability* with respect to preference or subjective value for Curly. So do the options of accepting \$1,010,000 and remaining honest. But the options of accepting \$1,000,000 and accepting \$1,010,000 do not. This is fine, though, because indiscriminability relations are not transitive. Assuming Curly's preferences for accepting lumps of money vary monotonically with the amount of money, there can be at most one number x such that accepting \$x is genuinely equally preferred to remaining honest, but there can be many values of x which are indiscriminable in respect of subjective value with remaining honest.

One response, I suppose, is to say that subjective matters like preference are "luminous" in Williamson's sense, so there shouldn't be a distinction between equal preference and indiscriminable preference. And we can avoid making such a distinction if we say that these are cases of incommensurability.

But even in subjective matters, it seems that there are cases where indiscriminability and identity come apart. This can happen with phenomenal sorites series, e.g. cases where experience e1 is phenomenally indistinguishable from e2, which is phenomenally indistinguishable from e3, but e1 is phenomenally distinguishable from e3. So there can be experiences which are phenomenally distinct but indiscriminable. It doesn't seem much weirder to think that one preference could be stronger than another but not discriminably stronger.

Alexander R Pruss said...

But wouldn't it be odd to say that there is an amount \$x such that it would be prudentially rational to choose honesty over \$x-1 but not over \$x? Maybe there is a vagueness worry here, though.

Brian Cutter said...

Yeah, I think the opponent of incommensurability should say that that's a vagueness issue and deal with it the way he deals with vagueness generally. If that's right, then presumably a similar issue will arise for the incommensurability view. Just consider the sorites series beginning with the pair and ending with the pair , proceeding in \$1 increments.

Brian Cutter said...

(The pairs didn't show up in my browser-- must have been interpreted as html code. They were: (taking \$1, being honest), (taking \$1,000,000, being honest).)