if all truths were scientific truths, we would be in deep trouble. We would then reject any claims that science cannot support. For example, do all human beings have equal value or worth? Either that makes no scientific sense (because objective or intrinsic value is not a scientific idea), or it is manifestly false, because science translates “value” into something like capacity or functioning, and then it is obvious that not all humans are equal.
I would argue that the agential view that treats us as reason-responsive free subjects is a subset of the naturalistic one, and that when naturalism and the agential view are in conflict, naturalism trumps. But I believe that values are compatible with naturalism.
Here’s how I’d put it. “Human equality” is not falsified by science’s insistence of objectivity, it is falsified by our practices and common sense observations. Simply put: we don’t treat all humans equally at present, so the claim of “human equality” is either nonsensical or aspirational. I take it that Levine’s worry is about a scientism that says that such values are nonsense, but I prefer to think of them as aspirations to extend our limited and fragile practices of equality beyond their current scope.
The real danger is not dissolving “human equality” into observable inequality (of status and capacity) but assuming “human equality” is settled while there is still work to be done in achieving the kingdom of ends. We don’t treat women equally to men, we don’t treat non-whites equally to whites, and we don’t treat foreigners equally to neighbors. But we should, and we do aspire to do better.
If equality is aspirational, we don’t need to adopt a non-naturalist metaphysics in order to justify it: we can explain the origin and practice of equality norms in our current practice naturalistically, and then explain our desire to extend those norms naturalistically as well. This is where P.F. Strawson, Elinor Ostrom, Cristina Bicchieri, Karen Stohr, and Jerry Gaus can help.