The Boundaries of the Moral (and Legal) Community

Abstract Over the last 250 years, both moral philosophy and ordinary moral opinion have witnessed a remarkable expansion of their conception of the “moral” community, that is, the community of creatures that are thought entitled to basic moral (and ultimately legal) consideration, whatever the precise details of what such consideration requires. “Being human” is what matters now in terms of membership in the moral community, not race, gender, religion, or, increasingly, sexual orientation. (Species membership—hence the “being human” —remains a barrier to entry, however.) How to explain these developments? According to “Whig Histories,” this is really a story of expanding moral knowledge. Just as we discovered that the laws of Newtonian mechanics govern the movement of mid-size physical objects, and that those same laws do not describe the behavior of quantum particles, so too we have discovered that chattel slavery is a grave moral wrong and that women have as much moral claim on the electoral vote as men. I argue against the Whig histories in favor of non-Whig histories that explain the expanding moral community in terms of biological, psychological, and economic developments, not increased moral knowledge. If the non-Whig histories are correct, should we expect the “species barrier” to membership in the moral community to fall? I argue for a skeptical answer.