I suspect the reason the moral circle seems to be expanding, is that we actually have a moral cone. Put someone in a situation where its the life of a close friend vs a distant stranger, and they will care about the close friend more. As the worlds standards of living rise, many people find that all their friends are already fine, so spare effort goes into helping the strangers. What we are seeing is our weaker preferences becoming more relevant as our strongest ones are satisfied.
Actually, in some social circles, you seem to draw a lot less criticism with an unusually wide circle than an unusually narrow one. This could be because if you only care about humans and they also care about chimps then they will still help humans nearly as much as you do. If you care about chimps and they don’t, they are likely to harm many chimps for little gain.
(Epistemic status, plausible conjecture)
I suspect the reason the moral circle seems to be expanding, is that we actually have a moral cone. Put someone in a situation where its the life of a close friend vs a distant stranger, and they will care about the close friend more. As the worlds standards of living rise, many people find that all their friends are already fine, so spare effort goes into helping the strangers. What we are seeing is our weaker preferences becoming more relevant as our strongest ones are satisfied.
Actually, in some social circles, you seem to draw a lot less criticism with an unusually wide circle than an unusually narrow one. This could be because if you only care about humans and they also care about chimps then they will still help humans nearly as much as you do. If you care about chimps and they don’t, they are likely to harm many chimps for little gain.