The Maxim and Determinism
- Posted by Andrew Bailey on Tuesday, March 27, 2007 at 5:04 PM
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9 Comments |
I recently gave a paper on the Kantian maxim that 'ought implies can.' Thanks are due, incidentally, to those who attended the talk; I received some helpful feedback and it will inform my future research into the topic.
That said, Brad Rettler comments on my paper in this post, and I'd like to interact with some of his thoughts.
Brad's central worry is that my affirmation of the maxim is incompatible with my views about free will, moral responsibility, and determinism. For the record, I am a semi-compatibilist. I think moral responsibility is compatible with determinism, while free will is not. I grant the point that my affirmation of the maxim stands in tension with my semi-compatibilsm. In this post, I try to state more precisely why this tension might turn out to be something worse, an incompatibility.
Brad's statement of the worry is as follows:
If determinism is true, then every action one performs, one necessarily performs (where necessity is physical necessity). But some of those actions, one ought not do. But if one ought not do some of those actions, then according to the Maxim one can refrain from doing them. But according to determinism, in fact one cannot refrain from doing them.
Thus, at least one of the following must be false: 1) S cannot refrain from performing a at t (given the laws of physics and the past, S must perform a at t). 2) S ought not have performed a at t (I think one cannot deny this without assuming the Maxim). 3) S could have refrained from performing a at t (this follows from (2) and the Maxim).
So, if we assume determinism, then (1) is true, and the Maxim is false.
The worry is real, but there are a few infelicities I comment on before trying to defuse it. First, determinism doesn't imply that anything that happens happens as a matter of physical necessity. It implies rather that given the actual past, anything that happens happens as a matter of physical necessity. We must not here confuse the necessity of consequence with the necessity of the consequent. Second, the formulation of the maxim I favor doesn't say that if someone ought to do something at a time, she can do so at that time. Rather, I have advocated a maxim with a tracing condition: if S ought to perform act a at t, then either S is able perform a at t or there is a time t* and an act b such that S can perform b at t* and were S to perform b at t*, it would be the case that S can perform a at t.
(3) doesnt' follow from (2) and the maxim, then. It does not follow from (2) and the maxim that I have advanced, at least. But something in the neighborhood does. Similarly, it's not enough to claim that determinism rules out someone's ability to do otherwise than she does. It must also be true that determinism rules out the ability to do anything such that doing so enables one to do otherwise than she in fact does. Following is my attempt to state with just a little rigor the argument Brad proposes:
1. If determinism is true, then no one is able to either do otherwise than she actually does, nor is anyone able to do anything such that had she done it, she would have been able to do otherwise than she actually does. (assumed, incompatibilism about free will and determinism)
2. Determinism is true. (assume for reductio)
3. Someone ought to have done otherwise than she actually does. (assumed)
4. If someone ought to have done otherwise than she actually does, then someone is able to either do otherwise than she actually does, or someone is able to do something such that had she done it, someone would have been able to do otherwise than she actually does. (from the Maxim)
5. Therefore, no one is able to either do otherwise than she actually does, nor is anyone able to do anything such that had she done it, someone would have been able to do otherwise than she actually does (from 1 and 2).
6. Therefore, someone is able to either do otherwise than she actually does, or someone is able to do something such that had she done it, someone would have been able to do otherwise than she actually does. (from 3 and 4)
7. Oops. (from 5 and 6)
Suppose I got the worry right (did I, Brad?); in my next related post, I'll try and defuse it.
9 Comments:
bradley james at 6:25 PM said... This post has been removed by the author.
bradley james at 6:27 PM said... That looks right. There's a lot of "someone"s and "anyone"s, so I'll try to restate it perhaps a bit more precisely:
1) If determinism is true, then S is not able to refrain from a, nor was S able to do any b such that had S done b, S would have been able to do otherwise than a. (assumed, incompatibilism about free will and determinism)
2. Determinism is true. (assume for reductio)
3. S ought to do otherwise than a. (assumed)
4. If S ought to do otherwise than a, then either S is able to do otherwise than a, or S was able to do something b such that had she done b, S would have been able to do otherwise than a. (from the Maxim)
5. Therefore, S is not able to either do otherwise than a, nor was S able to do anything b such that had S done b, S would have been able to do otherwise than a (from 1 and 2).
6. Therefore, S is able to either do otherwise than a, or S was able to do something b such that had S done b, S would have been able to do otherwise than a. (from 3 and 4)
7. Oops. (from 5 and 6)
I look forward to your response.
at 11:16 AM said... I too am interested to see your reply. Also, let me remind you of another worry for your committment to both semi-compatibilism and the maxim. PAP is false, but the Maxim entails PAP--at least a blameworthiness reading of PAP.
Here's one way to state the derivation that I favor. First, here is a principle:
(BMO) A person is morally blameworthy for failing to do X at T only if he was morally obligated to do X at T, and a person is morally blameworthy for doing X′ at T′ only if he was morally obligated not to do X′ at T′.
This principle provides the conceptually necessary link between blameworthiness and moral obligation, and when taken in conjunction with the Maxim entails a version of PAP:
(1) A person is morally blameworthy for failing to do X at T only if he was morally obligated to do X at T (from BMO)
(2) A person was morally obligated to do X at T only if he could have done X at T (from the Maxim)
(3) Therefore, a person is morally blameworthy for failing to do X at T only if he could have done X at T (version of PAP)
This derivation avoids Yaffe's objection to Copp, and though it does not show that the Maxim entails PAP exactly, (3) is a version of PAP that, as I understand your position, you're comitted to denying. (For what its worth, I think PAP for actions and not merely omissions can be derived from the maxim too, but I'm still sometimes sensative to Yaffe's worries).
Andrew Bailey at 2:51 PM said... I had a reply to these arguments. I thought I did, at least. But after mulling over these issues for most of the day, I'm no longer sure.
Perhaps I'll have to change my mind about the maxim, incompatibilism about free will and determinism, or compatibilism about moral responsibility and determinism.
I'm increasingly of the mind that these views are hard to consistently hold. So thanks, Brad and Justin, I just might be on the verge of a discovery as the result of this conversation! =)
at 11:38 PM said... I don't like the maxim or compatibilism (of either the free will or the moral responsibility variety) but as much as I hate to say it, it seems to me that if you have to give something up, it ought to be the maxim (this is what Fischer gives up). It seems to me the least important and the least motivated of the three theses.
bradley james at 2:06 PM said... My intuition is the opposite of Justin's. I don't like thinking that I ought to do something that I simply am unable to do. So, I'm inclined to accept the Maxim.
Perhaps an option is embracing virtue theory, which may make the Maxim irrelevant, and you can keep semi-compatibilism.
at 4:55 PM said... Brad,
Since I do embrace virtue theory, that is certainly one motivation for rejecting the maxim (or at least for not needing it), but another thing that motivates me to reject it is the sort of argument I given above. Because I accept a Frankfurt-inspired critique of PAP, and because the Maxim entails PAP, it seems to me that the maxim must be false. But may be you don't think as highly of Frankfurt as Andrew and I do, or perhaps you think some premise in the above derivation is false?
bradley james at 10:32 AM said... Well, were I to subscribe to a deontological ethic, it would seem to me that the Maxim would have to be true. That, coupled with the fact that I find Frankfurt-style counter-examples a bit ludicrous, would cause me to embrace some version of PAP.
at 8:31 PM said... Andrew,
In the Christian tradition, couldn't you "trace" responsibility back to Adam's fall where, arguably, man was able to do otherwise?
