There isn't any "harm" - that's the entire point. It just feels wrong at a gut level. The example was specifically chosen to be something that did not upset "harm avoidance" or "egalitarianism" or "autonomy" (in the john haidt sense). I was trying to think of a world in which I might be the conservative one. In this case, I think that the notion of a human without negative effect is hitting some sort of psychological Uncanny Valley between human and alien for me. Maybe it violates some sort of purity norm? Or perhaps it causes individuals to in some senses leave the "in-group" by becoming less similar to me? The truth is that the strangeness would probably wear off after repeated exposure. I only had to think about the idea for a small amount of time before realizing it wasn't really as bad as it seemed at first. But I can I imagine that if I hadn't ever considered the idea in my youth, an older version of me would no longer be cognitively flexible enough to consider it as acceptable behavior. This is probably how conservatives feel with homosexuality. (And just the same way, if you take a young conservative who doesn't take any religious scriptures literally, and you give them repeated exposure, they tend to change their mind unless religion somehow interferes). (If everyone did it, there might be ...not harm, but dis-utility. It wouldn't be my optimal universe, though perhaps it wouldn't be worse than the present. I think that I consider diversity of experiences intrinsically valuable, so I'd feel like something intrinsic to humanity was lost if at least some toned-down brands of negative affect weren't preserved in at least some people. A more obvious problem is that it might be boring...I'm not sure whether the fact that they wouldn't find it boring makes it better or worse. I guess I'd be happy for them, but I wouldn't identify myself, or humanity, with them as much.) Yes... I think what bothers me most is that it is a subtraction. It's one fewer emotion o