Constructivism, Expressivism and Ethical Knowledge

In the contemporary metaethical debate, expressivist (Blackburn, Gibbard) and constructivist (Korsgaard, Street) views can be viewed as inspired by irrealist ideas from Hume and Kant respectively. One realist response to these contemporary irrealist views is to argue that they are inconsistent with obvious surface-level appearances of ordinary ethical thought and discourse, especially the fact that we talk and act as if there is ethical knowledge . In this paper, I explore some constructivist and expressivist options for responding to this objection. My conclusion is that, although both constructivists and expressivists can capture other surface-level features of ethical thought and discourse, the possibility of ethical knowledge causes special problems for these versions of irrealism. I end with some comments about where I think irrealists should begin to look for a response to these special problems, which points, somewhat surprisingly, towards an alternative inferentialist form of irrealism about epistemic and ethical thought and discourse, which is inspired by Sellars