I'm in Chapter 5 of Brandom's Making it Explicit (have read all three of his shorter books and big chunks of Tales of the Mighty Dead), and I'm really caught up on something that should be basic.
I just don't get what Brandom means by "entitlement." On the one hand commitment and permissibility are treated as a species of obligation and permissibility, but on the other hand he wants it to be the case that being entitled requires either the ability to produce a justification or to defer to someone who can.
For the life of me, I can't see how both of these are true, at least without serious logical revision. (1) If commitment and permissibility are a species of obligation and permissibility, then it should follow from one being not committed to believing that P, that one is entitled to believe that P is not the case, (2) if entitlement carries with it the responsibility to defer to the right person or produce a justification yourself, then merely not being committed to something does not entitle one to believe it's negation. I mean you should just sit on the fence for lots of beliefs you are not committed to.
One could possibly (though even this seems implausible to me) get out of this with logical revision. One way to be an intuitionist about modality is to accept that Possibly P is true if and only if there exists a possible world where P is true and that Necessary P is true if and only if P is true at all possible worlds, but to reject the claim that one can define the two in terms of each other (e.g. Possibly P equals Not Necessarily Not P, and vice versa), just because in intuitionistic logic it not being the case that something holds at all possible worlds does not entail that there exists a possible world where something is the case. This means that it not being necessary that P does not in general entail that it is possible that not P. But this is exactly analogous to it not being obligatory that P not entailing that it is permissible that not P. Which is the problematic inference for Brandom's notions of comittment and entitlement.
That doesn't seem that plausible to me just because intuitionism is inconsistent with their being third values. Not (P and ~P) is a theorem of intuitionist logic. But the problem with Brandom's notions is that there do seem to be claims that are such that we are not committed to them and that we are not entitled to their negations. By the analog with modal systems, this would be like a claim that is not true at any possible worlds and such that it is not the case that there is a possible world where it is false. To affirm this is to run afoul of intuitionistic logic.
I suspect I'm missing something.
