If you write down all we can know about pleasures (in the moment), and all we can know about pains, you may find parameters to compare (like “intensity”, or amount of neurotransmitters, or something else), but there would be no reason why people need to choose an exchange rate corresponding to some measured properties. I believe your point is that we “have reason” to pick intensity here, but I don’t see why it is rationally required of beings to care about it, and I believe empirically, many people do not care about it, and certainly you could construct artificial minds that don’t care about it.
Pleasure is not what makes decisions for us. It is the desire/craving for pleasure, and there is no reason why a craving for a specific amount of pleasure needs to always come with the same force in different minds, even if the circumstances are otherwise equal. There is also no reason why this has to be true of suffering, of course, and the corresponding desire to not have to suffer. People who value many other things strongly and who have a strong desire to stay alive, for instance, would not kill themselves even if their life mostly consists of suffering. And yet they would still be making perfectly consistent trades within different intensities and durations of suffering.
My general point is that whatever property you rely upon to make comparisons within pains you can also rely upon to make comparisons between pains and pleasures.
It seems to me that you are using intensity of desire to make comparisons within pains. If so, you can also use intensity of desire to make comparisons between pleasures and pains. That “there would be no reason why people need to choose an exchange rate corresponding to some measured properties” seems inadequate as a reply, since you could analogously argue that there is no reason why people should rely on those measured properties to make comparisons within pains.
However, if intensity of desire is not the property you are using to make comparisons within pains, just ignore the previous paragraph. My general point still stands: the property you are using, whichever it is, is also a property that you could use to make comparisons between pains and pleasures.
If you write down all we can know about pleasures (in the moment), and all we can know about pains, you may find parameters to compare (like “intensity”, or amount of neurotransmitters, or something else), but there would be no reason why people need to choose an exchange rate corresponding to some measured properties. I believe your point is that we “have reason” to pick intensity here, but I don’t see why it is rationally required of beings to care about it, and I believe empirically, many people do not care about it, and certainly you could construct artificial minds that don’t care about it.
Pleasure is not what makes decisions for us. It is the desire/craving for pleasure, and there is no reason why a craving for a specific amount of pleasure needs to always come with the same force in different minds, even if the circumstances are otherwise equal. There is also no reason why this has to be true of suffering, of course, and the corresponding desire to not have to suffer. People who value many other things strongly and who have a strong desire to stay alive, for instance, would not kill themselves even if their life mostly consists of suffering. And yet they would still be making perfectly consistent trades within different intensities and durations of suffering.
My general point is that whatever property you rely upon to make comparisons within pains you can also rely upon to make comparisons between pains and pleasures.
It seems to me that you are using intensity of desire to make comparisons within pains. If so, you can also use intensity of desire to make comparisons between pleasures and pains. That “there would be no reason why people need to choose an exchange rate corresponding to some measured properties” seems inadequate as a reply, since you could analogously argue that there is no reason why people should rely on those measured properties to make comparisons within pains.
However, if intensity of desire is not the property you are using to make comparisons within pains, just ignore the previous paragraph. My general point still stands: the property you are using, whichever it is, is also a property that you could use to make comparisons between pains and pleasures.