Five months later...

Yeah, a lack of reply notification's a real pain in the rear.

It seems to me that this thread of the debate has come down to "Should we consider babies to be people?" There are, broadly, two ways of settling this question: moving up the ladder of abstraction, or moving down. That is, we can answer this by attempting to define 'people' in terms of other, broader terms (this being the former case) or by defining 'people' via the listing of examples of things which we all agree are or are not people and then trying to decide by inspection in which category 'babies' belong.

Edit: You can skip to the next break line if you're not interested in reading about the methodological component so much as you are continuing the infants argument.

What we're doing here, ideally, is pattern matching. I present you with a pattern and part of that pattern is what I'm talking about. I present you with another pattern where some things have changed and the parts of the pattern I want to talk about are the same in that one. And I suppose to be strict we'd have to present you with patterns that are fairly similar and express disapproval for those.

Because we have a large set of existing patterns that we both know about - properties - it's a lot quicker to make reference to some of those patterns than it is to continue to flesh out our lists to play guess the commonality. We can still do it both ways, as long as we can still head back down the abstraction pile fairly quickly. Compressing the search space by abstract reference to elements of patterns that members of the set share, is not the same thing as starting off with a word alone and then trying to decide on the pattern and then fit the members to that set.

If you cannot do that exercise, if you cannot explicitly declare at least some of the commonalities you're talking about, then it leads me to believe that your definition is incoherent. The odds that, with our vast set of shared patterns - with our language that allows us to do this compression - that you can't come up with at least a fairly rough definition fairly quickly seem remote.

If I wanted to define humans for instance - "Most numerous group of bipedal tools users on Earth." That was a lot quicker than having to define humans by providing examples of different creatures. We can only think the way we do because we have these little compression tricks that let us leap around the search space, abstraction doesn't have to lead to more confusion - as long as your terms refer to things that people have experience with.

Whereas if I provided you a selection of human genetic structures - while my terms would refer exactly, while I'd even be able to stick you in front of a machine and point to it directly - would you even recognise it without going to a computer? I wouldn't. The reference falls beyond the level of my experience.

I don't see why you think my definition needs to be complete. We have very few exact definitions for anything; I couldn't exactly define what I mean by human. Even by reference to genetic structure I've no idea where it would make sense to set the deviation from any specific example that makes you human or not human.

But let's go with your approach:

It seems to me that mentally disabled people belong on the people list. And babies seem more similar to mentally disabled people than they do to pigs and stones.

This is entirely orthogonal to the point I was trying to make. Keep in mind, most societies invented misogyny pretty quick too. Rather, I doubt that you personally, raised in a society much like this one except without the taboo on killing infants, would have come to the conclusion that killing infants is a moral wrong.

Well, no, but you could make that argument about anything. I raised in a society just like this one but without taboo X would never create taboo X on my own, taboos are created by their effects on society. It's the fact that society would not have been like this one without taboo X that makes it taboo in the first place.