I bite the bullet: I aim to use only goal-based thinking. (I dare say I don’t completely succeed.) I may have goals like “enjoy eating a tasty meal” or “stop feeling hungry” but those are still goals rather than what you’re calling desires.
I don’t think the two examples in your final paragraph are isomorphic, and I think they can be seen to be non-isomorphic in purely goal-based terms.
All else being equal, I prefer people to live rather than die, and I prefer that my preferences be satisfied. Taking a murder-pill would mean that more people die (at my hand, even) or that my preferences go unsatisfied, or both. So (all else being equal) I don’t want to take the murder-pill.
All else being equal, I prefer to eat things that I like and not things that I don’t like. I (hypothetically) don’t like spinach right now, so I don’t eat spinach. But if I suddenly started liking spinach, I would become able to eat spinach and thereby eat things I like rather than things I don’t. So I would expect to have more of my preferences satisfied if I started liking spinach. So (all else being equal) I do want to start liking spinach.
All of this is a matter of goals rather than (in your sense) desires. I want people to live, I want to have my preferences satisfied, I want to eat things I like, I want not to eat things I dislike.
“But”, I hear you cry, “you could equally well say in the first place ‘I prefer to live according to my moral principles, and at present those principles include not murdering people, but if I took the pill those preferences would change.‘. And you could equally well say in the second place ‘I prefer not to eat spinach, and if I started liking spinach then I’d start doing that thing I prefer not to.’. And then you’d get the opposite conclusions.” But no, I could not equally well say those things: saying those things would give a wrong account of my preferences. Some of my preferences (e.g., more people living and fewer dying) are about the external world. Some (e.g., having enjoyable eating-experiences) are about my internal state. Some are a mixture of both. You can’t just swap one for the other.
(There’s a further complication, which is that—so it seems to me, and I know I’m not alone—moral values are not the same thing as preferences, even though they have a lot in common. I not only prefer people to live rather than die, I find it morally better that people live rather than die, and those are different mental phenomena.)
Some of my preferences (e.g., more people living and fewer dying) are about the external world. Some (e.g., having enjoyable eating-experiences) are about my internal state. Some are a mixture of both. You can’t just swap one for the other.
A way you might distinguish these experimentally: If you are correct about your preferences, you will sometimes want to get new desires. If for example you didn’t currently enjoy any kind of food, but prefer having enjoyable eating experiences, you will try to start enjoying some. The desire-agent wouldn’t.
I bite the bullet: I aim to use only goal-based thinking. (I dare say I don’t completely succeed.) I may have goals like “enjoy eating a tasty meal” or “stop feeling hungry” but those are still goals rather than what you’re calling desires.
I don’t think the two examples in your final paragraph are isomorphic, and I think they can be seen to be non-isomorphic in purely goal-based terms.
All else being equal, I prefer people to live rather than die, and I prefer that my preferences be satisfied. Taking a murder-pill would mean that more people die (at my hand, even) or that my preferences go unsatisfied, or both. So (all else being equal) I don’t want to take the murder-pill.
All else being equal, I prefer to eat things that I like and not things that I don’t like. I (hypothetically) don’t like spinach right now, so I don’t eat spinach. But if I suddenly started liking spinach, I would become able to eat spinach and thereby eat things I like rather than things I don’t. So I would expect to have more of my preferences satisfied if I started liking spinach. So (all else being equal) I do want to start liking spinach.
All of this is a matter of goals rather than (in your sense) desires. I want people to live, I want to have my preferences satisfied, I want to eat things I like, I want not to eat things I dislike.
“But”, I hear you cry, “you could equally well say in the first place ‘I prefer to live according to my moral principles, and at present those principles include not murdering people, but if I took the pill those preferences would change.‘. And you could equally well say in the second place ‘I prefer not to eat spinach, and if I started liking spinach then I’d start doing that thing I prefer not to.’. And then you’d get the opposite conclusions.” But no, I could not equally well say those things: saying those things would give a wrong account of my preferences. Some of my preferences (e.g., more people living and fewer dying) are about the external world. Some (e.g., having enjoyable eating-experiences) are about my internal state. Some are a mixture of both. You can’t just swap one for the other.
(There’s a further complication, which is that—so it seems to me, and I know I’m not alone—moral values are not the same thing as preferences, even though they have a lot in common. I not only prefer people to live rather than die, I find it morally better that people live rather than die, and those are different mental phenomena.)
A way you might distinguish these experimentally: If you are correct about your preferences, you will sometimes want to get new desires. If for example you didn’t currently enjoy any kind of food, but prefer having enjoyable eating experiences, you will try to start enjoying some. The desire-agent wouldn’t.