Blackcatter:

What this discussion proves is that it is nearly impossible to define groups of humans

Or that it's far too easy to define groups of humans.

But whether or not it's a good idea, people will continue to think of themselves -- and others -- as members of groups. The borders may be fuzzy, the uses made of the groups may be horrible, but categorizing will be with us forever, I'm afraid. It's part of what makes language possible. Any time you use a noun or an adjective, you create a group. You might even say groupifying is an identifying mark of human beings.

What is needed is a way to ensure that in our groupifying, we don't end up treating some groups (of human beings) as worthy of human dignity, civil rights, etc., than others.

IMHO of course.

Alex