All right, here is my reply:
David wrote:Electrons seem to exist only through their influence on other particles. But then you have a problem of circularity, or of regression: if a particle exists only through its influence on other particles, and these in turn have no more existence than that, what can the word "exist" mean in the first place? …since our current physical worldview tells us that particle detectors, papers and salaries are themselves only just collections of particles, this concrete, down-to-earth reality itself seems to sit on a shaky basis.
First, I didn’t realize that quantum physics said this sort of thing about all particles – I’ve mainly heard it about electrons. Does it say that really all particles only exist in their influence on other particles? If so, my current thought is that either this is contradictory, in which case it can’t be true, or it is just counterintuitive, in which case at the quantum level everything just exists in terms of how it influences other things, and this system of interactions makes up objects at the Newtonian level, which can exist whether or not they influence other things.
Regardless, I see your point that the concept of an electron is unclear. Maybe you could say that electrons are scientists’ current theory for what is causing a number of specific results we see in the real world? And maybe the cause of such results is something physical, maybe it is something which only exists through its influence on other particles. So when we talk about whether electrons exist, we are asking whether various different theories of electrons are correct. These theories may say they are particles, or maybe something else, but they are all theories which are ultimately about results seen in the laboratory and the wider world, and they all have claims which can be true or false (at least, all the coherent theories do).
But I don’t know what it would mean for a claim about moral facts to be true or false. Not only am I ignorant about what kind of thing moral facts might be; I don’t even know what the term “moral fact” might mean. Does “moral fact” mean a value which everyone has a motivation to have? Does it mean a value which helps us get along with others? Does it mean a norm which most societies have for their members to follow?
Finally, another thing about electrons is that we know how to learn things about their properties, even if we don’t know exactly what kinds of things they are. Scientists can conduct experiments to learn more about the behavior, if not the nature, of electrons. I'm not sure I understand what "moral facts" are enough to figure out how to know anything about them. How would you determine what is in fact moral?
David wrote:On the other hand, the prescriptive fact that I should try to wrap this answer up quickly and get to bed, because I must get up early, seems to have a quite clear meaning.
I understand the prescriptive statement that you shouldn’t stay up late, but I don’t understand what a “prescriptive fact” is. That you "should" go to bed seems to mean that if you decide stay up late tonight you will not like the result of that decision: being tired in the morning. Even if you didn’t care about being tired in the morning, maybe you would care about being able to think clearly in the morning, being healthy, or having enough energy to play soccer, or being happy; all of these desires would be undermined by not getting enough sleep. But if you didn’t care about any of these things, it wouldn’t make sense to me for you to say “I shouldn’t stay up late.” So I don’t think the idea of a prescriptive fact is required to make sense of your sentence.
David wrote:Now I don't necessarily want to argue for some kind of "idealist" view according to which prescriptions, ethics, sensations and so on are the only real things, hard "reality" being an illusion. It's just that both sides of the coin -- the "descriptive" one and the "prescriptive" one -- appear to me equally problematic, and I think it's really unfair, and heavily biased, to accept outright the former as having a clear meaning while poo-pooing the latter as being just fairy that by their very nature can only be the effect of wishful thinking programmed by our genes.
I don't think that sensations, emotions, attitudes etc. are less real than physical things. If anything, they are more real - they are the only things we have direct access to. I'm not coming from Daniel Dennett-like perspective here. I'm coming from a Humean perspective – I don't think there is any way around the fact-value dichotomy.
Here is one way to think about it: Suppose it turns out that there are "moral facts", whatever those things would be. Why should I care? I presume those moral facts would form sort of moral code about how I should live my life. Yet why should I decide to live my life that way? For example, people might believe that God exists and commands us to live a certain way, but they still have to decide whether or not to follow God.
My utilitarianism can be divided into 3 things: a goal which I try to achieve, a replacement for parts of the "folk" morality I had before utilitarianism, and a guide for what I should argue is "moral" with other people. If at some point we discovered "moral facts", I might not decide to pursue the goals they stated, to put them into the pre-existing schema for morality which I already have, or to claim that those "moral facts" told us what is morality right. In what sense would I be wrong?
David wrote: There is no logical contradiction in holding that "there are no prescriptions", but if that were so, we would really have no reason to do anything at all (nor not to do it); and no one believes that, since we do have to decide what to do (or to do nothing, which is something too)...
I don't think it's true at all that when we decide act it is only to fulfill our desires. In the morning I often have no desire at all to get up and go to work, yet I do it. Deliberation is not at all limited to finding the best way to satisfy our pre-determined aims; deliberation is often about the aims themselves.
OK, but do you admit that we often have a reason to do something without believing that the reason was true or false? That is, we believe it is true that our action will achieve our aims, but we don't believe that our aims are true or false? For example, say I am trying to decide whether to buy a car, and I want to do what my father would do in this situation. I decide that he would buy the car, so I have a reason to buy the car. If I didn’t want to do what my father would do in this situation, I wouldn’t have a reason to buy the car. Therefore my reason is contingent on my desire to act as my father would.
If you go to work even though you have no desire to, there are two explanations which are consistent with my view. First, you are not thinking about it, it is just habit. Second, you try to decide whether to go to work, and while you have a desire to stay home, you also have a desire to keep your job (or make money, or finish your project, or do your duty), and this second desire wins out.
I do admit that it is possible that people could act without having any desire to act – whether or not we do or not is a question for psychology. But we still have to be motivated to act – that is, there must be something which causes us to act, even if it is not a desire. And a belief cannot motivate in itself. Suppose you have the thought “X is a moral fact.” If that though causes you to act in accordance with X, there must be something in your brain which inclines you to follow rules which you think are moral facts. That is, you must have a motivation to follow such rules. If you don’t have such a motivation, then the thought “X is a moral fact” is not going to make you act.
So you might not consciously desire to follow rules you believe to be moral facts. But your acting on a moral belief is still contingent on some motivation to do so. You could easily not have that motivation. True, most people probably wouldn’t believe something was a moral fact if they have absolutely no motivation to act on the basis of this belief. But that actually supports my point that motivation is an essential element in action.
This argument holds for deliberation about aims as well. Deliberation about aims might be based on desires. For example, I want to help other people, and I want to follow a code of ethics which is logically consistent. If I deliberate about what I should do with these desires in mind, I might arrive at utilitarianism. This is an example of desires forming the motivation for my moral aim.
Now suppose desires do not enter into my deliberation. I posit certain principles a moral code might conform to, such as care for others and logical consistency. I decide that utilitarianism best meets these principles. But what motivates me to adopt utilitarian goals as my aim? If I am not motivated to follow a code which conforms to the principles of caring and logical consistency, then my deliberation was for nothing.
Finally, I don’t think you can decide to act for a
reason if you have no motivating desire or aim. Your goal might just be to act bravely, but if you have no aim you can’t have a reason to do anything. Can you come up with an example of someone having a reason to do something without presupposing a goal or desire which he is trying to achieve (for example, he is trying to make money, therefore he sells the car), or simply a thing which he is trying to do (for example, he is trying to do what his father would have done in this situation, after deliberation he decides his father would sell the car, and therefore he sells the car)?
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