How does Simon Blackburn’s quasi-realism try to explain moral language without special moral facts?

Simon Blackburn’s quasi-realism is a sophisticated development of expressivism and projectivism that seeks to explain moral language without relying on a domain of nonnatural moral facts.1

Rather than viewing moral judgments as mere expressions of approval or disapproval—as earlier emotivists did—Blackburn argues that moral judgments are "projections" of our attitudes onto the world. We treat these projections as if they correspond to objective facts, even though they are actually products of our moral attitudes.12

Blackburn contends that there is no need to abandon this "objectivist" way of speaking. By treating ethical propositions as true or false, we facilitate the serious, reflective discussion necessary for navigating our moral lives. In this framework, morality is treated as if it were objective to serve a functional purpose in human discourse, despite the absence of a distinct, external realm of moral truths.21