That’s a similar case to the example I gave, and it has the same features that (I think) make it unhelpful as a defence of Phil’s argument: (1) in that situation, the past opinions that we think were better than our present ones are ones we don’t know (and therefore can’t choose to adopt), and (2) pretty much exactly the same scenario works pretty much exactly as well for values as for opinions.
That’s a similar case to the example I gave, and it has the same features that (I think) make it unhelpful as a defence of Phil’s argument: (1) in that situation, the past opinions that we think were better than our present ones are ones we don’t know (and therefore can’t choose to adopt), and (2) pretty much exactly the same scenario works pretty much exactly as well for values as for opinions.