The Barefoot Bum has now also responded to Brian Leiter's poor arguments against Preference Satisfaction. We pretty much agree over Leiter but this has triggered a couple of thoughts for posts. Today I will examine the concept of prudence. When it comes to case #1 where Leiter argues that the addict who just satisfies his preference may decrease his well-being, we both agree that the issue here is of prudence and that one cannot examine preferences in isolation. However we have been using different conceptions of prudence.
One view of prudence is that it is about concern over one's future self - one's future preferences or desires - and the difficulty is specifically over desires that do not exist now but will or are most likely to. Now since people seek to fulfil the more and stronger of their desires that do exist and since such future desires do not yet exist, then they will not seek to fulfil such non-existent desires, so how could they think or behave prudently? One suggestion is that they (could) have a present desire that one's future self's desires be fulfilled, that someone who lacks such a concern over one's future self cannot think prudently and someone who has such a desires can. Barefoot, correctly, calls this altruism, as having this desire requires the sacrifice of one's present person to the benefit of one's future person. The problem is that in one sense the present person and future person are two different people, so why should one be altruistic to this other person, why should one exhibit empathy for the future person? This is certainly a good question, certainly if one accepts the presuppositions that prudence's main issue is over the present non existence of future desires. I do not accept this, or rather side step this, and intend to show that this is good enough for the issue at hand.
Let us return to the fact the people seek to fulfill the more and stronger of their desires. The way I use "prudence" is to examine those desires that were not the more and stronger, that is the desires that lost out yet they still exist now in the present person. The fact that one desire was acted upon, that it was the more and stronger of the desires available in the person when they acted, does not mean this was the prudentially best choice out of those desires that is with respect to one's present desires - desires that do exist in the person - that is what is more and stronger can diverge from what is most prudent.(Note that this includes the idea of akrasia - although this divergence is not just akrasia- weakness of will). How can this be? Well the question of prudence can be asked by evaluating the desire acted upon with respect to its material effects on all the other existing desires of the person, the ones not acted upon. As for why the person did not act prudently the same types of issues that challenge moral or legal actions can be applied here. Did they forsee the outcomes on their other desires? Were they reckless or negligent in their reasoning? And so on.
Three other points need to be emphasized, first is that desires are persistent entities. They may not be active but can still exist in the present person - this certainly is one reason why they can be overwhelmed - but of course this usually has practical benefits - one is not hungry all the time, the desire persists and exists but is only activated in certain situations. The second is that desires can take a while to fulfil sometimes only in an incremental fashion - such as studying for a degree over a few years. That is desires over long-term interests can and do exist in the present person now as well as desires for short-term or immediate fulfilment. And finally some may indeed lack desire that it is in their prudential interest to have. It is quite possible, presumably, say, that an addict has managed to extinguish pretty much all other desires except the desire to fulfil their addiction. (This is an externalist position - that an addict may lack desires it is in their prudential interest to have and one form of treatment might be to instil such desires in the addict).
Lets now look at Barefoot's cigarette example. Like Barefoot, this is fortunately my only experiential understanding of addiction (although I would prefer to have none, so this is still unfortunate). I am well aware of the dangers of me smoking now and directly experience the negative side effects - coughing, damage to my wallet, smoking outside it the freezing cold and so. Still I have never stopped based on arguments over the damage to my future self, as plausible as they sound, they do not work, I can only care about my present desires. One could say that smoking clouds any attempt to have empathy or be altruistic for one future self? Anyway I am stopping at present becuase, due to the innovations of science, I have an alternate means to fulfil the state of affairs generated by this addiction, I have disabused myself of the belief that smoking a cigarette is the only means - I am using nicotine patches. (At least nowadays such a belief is false -before the invention of patches it might have been but then there was snuff etc.) Now whilst I do intent to fully stop, in the meantime using patches to fulfil this state of affairs is more prudential than smoking a cigarette. I still have the same more and stronger desire but fulfil it in a way that does not thwart as many of my other desires. Hopefully this demonstrates the point over the divergence between prudence and what one does - without relying on non-existent desires.
Hopefull the above goes to show that one can practically apply prudential reasoning without worrying or being blocked over how to be alturistically motivated over the presently non existent future desires of a future self.