Sure, but what I'm saying is that this doesn't happen in a way that allows your neurons to encode value for a 140-volt electrical shock.

Ah, understood.

But I'm not trying to show why encoding values for propositions is problematic. I'm trying to say that the brain does not encode values for objective intensities of stimuli.

Okay. I understand that it's a fact that the brain doesn't encode values for objective intensities of sensory stimuli. My puzzlement comes from when you say

Thus we smack headlong into another problem for human values and their extrapolation.

I don't see the fact as an additional problem for a theory of human values. But there's no point in arguing about this, as I think we'd both agree that any theory of human values would have to accommodate the fact.