We don’t capitalize “human” because as of now there are no other intelligent species we have relationships with on that level; there’s no need to add that level of “respect” to the word. But if we did make first contact with an intelligent alien species, I wouldn’t be surprised if cultural conventions like whether or not to capitalize the names of sentient species became a thing.

[–] Skua@kbin.earth 1 points 2 days ago

I'm not sure I see why we'd do that when we don't already draw the distinction that way between ourselves and other animals. The only way I see "Human" as a proper noun in English is if we wind up uniting under "the Human Federation" or something like that and it specifically becomes the demonym of the polity we belong to