All properties are natural properties. The natural/cultural distinction should be dropped. Still, there are good enough reasons to consider some form of relativism about our theories and the way they are supposed to engage with the world. Why is it that we get difference in taste, moral views and else?
An answer comes from the realization that believing something is a natural function of living organism; together with the claim that living organisms are constantly changing their constitution depending on how they engage with their environment (and of course depending on what environment they live in). Different beliefs and different tastes will naturally appear for different organisms in different environments. What is still left to account for is the idea of sameness of environment.
In a strict sense, no two organisms share the same environment. Getting the environment fine grained enough here will be sufficient to account for that sort of relativism that one was looking for from the very beginning. It can easily do the work that centered worlds are doing in possible-world semantics. What then could be the difference?
Answer: there is no need for a heavy ontological commitment; neither for possible worlds as concreta, neither for universals, nor un-instantiated universals.
Somehow, without thinking about this too much, it seems to me that one gets Lewi’s paradise on a very cheap price.
Note: this does not give place to some protagorian relativism. It is important to keep in mind that the way in which our natural conceptual capacities work relies on the existence of other organisms of the same sort. The central claim here would be that for there to be an organism that comes up with representations of the world, such organism must be able to use concepts in a self-ascriptive way. But for it to be possible to self-ascribe a concept there must be a community of objects within the extension of the concept in use.
Briefly: the claim is that something like a community of objects are required for an organism to be capable of engaging in the linguistic practices that we know to have.
A consequence of this is that all normative systems must be understood relative to communities and not relative to individuals. For such a view it is incorrect to talk about individual moral systems, and the internalization of these systems must be taken care with a lot of detail.
