Tuesday, October 5, 2010

"Can" and the five minute mile

It used to be fashionable for compatibilists to analyze "x can A" as something like:

  1. x would A if x wanted to
(or even worse: "x could A if x wanted to"[note 1]). Here's a sentence we can imagine a coach encouraging x by saying:
  1. You would run a five minute mile if you really wanted to.
The coach might back this up by saying that she is sure that you would run a five minute mile when chased by a hungry bear. We should not take (1) to entail:
  1. You can run a five minute mile.
To go from (1) to (2), we would need to know that you are capable of inducing in yourself, in the absence of a hungry bear, the kind of motivation that would be required for you to run a five minute mile. In other words, (1) only yields (2) if we suppose that you can get himself to "really want" to run. We all know that there are things that people in ordinary psychological situations can't do, but that they could do in motivationally extraordinary ones, and we do not attribute these things as abilities simpliciter to them.

I submit that for the same reason that (1) does not entail (2), (0) does not entail that x can A. Just as (1) raises the question whether you could get yourself to really want to, so too (0) raises the question whether you could get yourself to want to.

Objection 1: There is a difference between conditioning on "wanted to" and conditioning on "really wanted to". The latter condition requires a particular degree of desire while the former simply attributes the desire. One cannot infer "x can A" from "x would A if x wanted to with degree D", but one can infer it from "x would A if x wanted to".

Response: Actually, the "wanted to" in (0) has to say something about the degree of desire, or else "x can A" would not entail (0). For it can be true that x can A and x wants to A, but x does not A, because x does not sufficiently want to A. So the "wanted to" in (0) has to rule out, for instance, the case where x wants to A, but only just a little.

Objection 2: Claim (0) is a straw man. What really should be said is something like:

  1. x would A if x wanted to A more than x wanted any alternative.

Response: But now the bear case comes back. For among the alternatives to running a five minute mile, for someone who does not habitually do so, there is the avoidance of severe exhaustion and pain. It could well be that only a threat like a hungry bear could make one want to run a five minute mile more than one wants to avoid these kinds of alternatives. And in that case, (3) could be true, because if one wanted to A more than one wanted any alternatives, that was because one's reason for Aing was at least as motivating as a hungry bear. But it could still be false to say that one could run the five minute mile sans hungry bear (or equivalent).

I should end by saying that I am not that happy with my response to (3). I fear it is finkish.[note 2]

3 comments:

  1. I am not necessarily a big fan of conditional analyses of ‘can’ but this doesn’t seem like a great argument. Start with what I take to be undisputed (is it?) that

    (4) I would run a 5-minute mile if a hungry bear was chasing me

    Entails

    (2) I can run a 5-minute mile.

    I take it that what you want to argue is that, even if (1) is true of many people, (2) is not. But now consider that we might arrive at (4) through

    (5) If a hungry bear was chasing me, I would really want to run a 5-min mile, and
    (1) If I really wanted to run a 5-min mile, I would.

    (Hypothetical syllogism doesn’t work on subjunctives, so it’s not entailment, but (1)+(5)=(4) seems like a good inference.) Now suppose, in the actual world, that (5) and (1) are both true of many people. If so, then (4) is true of them, and therefore so is (2).

    ReplyDelete
  2. Actually, Heath, I was taking it that (4) does not entail (2). Someone who can only run a 5-minute mile if a hungry bear was chasing her is not a person who can run a 5-minute mile (unless in fact the bear is there). It's like the case of someone who can only run a 5-minute mile if she takes drug D. Unless she is capable of taking drug D, we don't conclude that she can run a 5-minute mile.

    ReplyDelete
  3. OK, I don't share the intuition that the cases are alike, but I don't know how to argue it.

    ReplyDelete