I can see that you might question the usefulness of the notion of a "reason for action" as something over and above the notion of "ought", but I don't see a better case for thinking that "reason for action" is confused.
The main worry here seems to have to do with categorical reasons for action. Diagnostic question: are these more troubling/confused than categorical "ought" statements? If so, why?
Perhaps I should note that philosophers talking this way make a distinction between "motivating reasons" and "normative reasons". A normative reason to do A is a good reason to do A, something that would help explain why you ought to do A, or something that counts in favor of doing A. A motivating reason just helps explain why someone did, in fact, do A. One of my motivating reasons for killing my mother might be to prevent her from being happy. By saying this, I do not suggest that this is a normative reason to kill my mother. It could also be that R would be a normative reason for me to A, but R does not motivate my to do A. (ata seems to assume otherwise, since ata is getting caught up with who these considerations would motivate. Whether reasons could work like this is a matter of philosophical controversy. Saying this more for others than you, Luke.)
Back to the main point, I am puzzled largely because the most natural ways of getting categorical oughts can get you categorical reasons. Example: simple total utilitarianism. On this view, R is a reason to do A if R is the fact that doing A would cause someone's well-being to increase. The strength of R is the extent to which that person's well-being increases. One weighs one's reasons by adding up all of their strengths. On then does the thing that one has most reason to do. (It's pretty clear in this case that the notion of a reason plays an inessential role in the theory. We can get by just fine with well-being, ought, causal notions, and addition.)
Utilitarianism, as always, is a simple case. But it seems like many categorical oughts can be thought of as being determined by weighing factors that count in favor of and count against the course of action in question. In these cases, we should be able to do something like what we did for util (though sometimes that method of weighing the reasons will be different/more complicated; in some bad cases, this might make the detour through reasons pointless).
The reasons framework seems a bit more natural in non-consequentialist cases. Imagine I try to maximize aggregate well-being, but I hate lying to do it. I might count the fact that an action would involve lying as a reason not to do it, but not believe that my lying makes the world worse. To get oughts out of a utility function instead, you might model my utility function as the result of adding up aggregate well-being and subtracting a factor that scales with the number of lies I would have to tell if I took the action in question. Again, it's pretty clear that you don't HAVE to think about things this way, but it is far from clear that this is confused/incoherent.
Perhaps the LW crowd is perplexed because people here take utility functions as primitive, whereas philosophers talking this way tend to take reasons as primitive and derive ought statements (and, on a very lucky day, utility functions) from them. This paper, which tries to help reasons folks and utility function folks understand/communicate with each other, might be helpful for anyone who cares much about this. My impression is that we clearly need utility functions, but don't necessarily need the reason talk. The main advantage to getting up on the reason talk would be trying to understand philosophers who talk that way, if that's important to you. (Much of the recent work in meta-ethics relies heavily on the notion of a normative reason, as I'm sure Luke knows.)
utilitymonster,
For the record, as a good old Humean I'm currently an internalist about reasons, which leaves me unable (I think) to endorse any form of utilitarianism, where utilitarianism is the view that we ought to maximize X. Why? Because internal reasons don't always, and perhaps rarely, support maximizing X, and I don't think external reasons for maximizing X exist. For example, I don't think X has intrinsic value (in Korsgaard's sense of "intrinsic value").
Thanks for the link to that paper on rational choice theories and decision theories!
Barring a major collapse of human civilization (due to nuclear war, asteroid impact, etc.), many experts expect the intelligence explosion Singularity to occur within 50-200 years.
That fact means that many philosophical problems, about which philosophers have argued for millennia, are suddenly very urgent.
Those concerned with the fate of the galaxy must say to the philosophers: "Too slow! Stop screwing around with transcendental ethics and qualitative epistemologies! Start thinking with the precision of an AI researcher and solve these problems!"
If a near-future AI will determine the fate of the galaxy, we need to figure out what values we ought to give it. Should it ensure animal welfare? Is growing the human population a good thing?
But those are questions of applied ethics. More fundamental are the questions about which normative ethics to give the AI: How would the AI decide if animal welfare or large human populations were good? What rulebook should it use to answer novel moral questions that arise in the future?
But even more fundamental are the questions of meta-ethics. What do moral terms mean? Do moral facts exist? What justifies one normative rulebook over the other?
The answers to these meta-ethical questions will determine the answers to the questions of normative ethics, which, if we are successful in planning the intelligence explosion, will determine the fate of the galaxy.
Eliezer Yudkowsky has put forward one meta-ethical theory, which informs his plan for Friendly AI: Coherent Extrapolated Volition. But what if that meta-ethical theory is wrong? The galaxy is at stake.
Princeton philosopher Richard Chappell worries about how Eliezer's meta-ethical theory depends on rigid designation, which in this context may amount to something like a semantic "trick." Previously and independently, an Oxford philosopher expressed the same worry to me in private.
Eliezer's theory also employs something like the method of reflective equilibrium, about which there are many grave concerns from Eliezer's fellow naturalists, including Richard Brandt, Richard Hare, Robert Cummins, Stephen Stich, and others.
My point is not to beat up on Eliezer's meta-ethical views. I don't even know if they're wrong. Eliezer is wickedly smart. He is highly trained in the skills of overcoming biases and properly proportioning beliefs to the evidence. He thinks with the precision of an AI researcher. In my opinion, that gives him large advantages over most philosophers. When Eliezer states and defends a particular view, I take that as significant Bayesian evidence for reforming my beliefs.
Rather, my point is that we need lots of smart people working on these meta-ethical questions. We need to solve these problems, and quickly. The universe will not wait for the pace of traditional philosophy to catch up.