Hundreds of fellow species of insects, birds, even a handful of primates. But at our level, only us. We want a companion species, something or some entity to be our equal, our make. If the Neanderthals or the Denisovans had survived as separate human species, and there were two or three of us humans on the planet, I think matters would be different.
As it stands, I think we want intellectual children and AI is that hope: like us, but different, so we’re no longer alone in a world full of non-human animals. It’s the same impulse that makes people treat their pets as children, as blood members of their family, and unironically refer to themselves as “mommy and daddy” to a dog or a cat that is their “baby”.
What if the Neanderthals had survived to the present? Since they’re able to interbreed with humans, aren’t they really just another race? What difference would it make to have Neanderthals in addition to whites, blacks, Asians, etc? We already don’t know how to deal with having all these races which are visibly different (and here I’m only speaking to the skin-level, nevermind any deeper differences). How much worse would we be if Elves showed up who were our superiors in every measurable way?
The truly alien minds are in our own homes: men and women. We are quite different, sometimes in large and sometimes subtle ways, and we cannot do without the other. Currently, we respond to this with denial, to the point where it took me years of living with a woman to unlearn the idea that we were just different skins slapped on the same basic mind template.
So yeah, we’re lonely, in the same way that Burke and Wills were starving; we’re misusing the resources that are there to fit the need. The trouble is that our current conception of “equal” does not allow room for “different,” so we just deny difference entirely. After all, in any reductionist materialistic view, a different thing is not equal. The Pauline view of equality as “valuable, yet different, parts of one body” is much more workable.
A babied toy dog is a clear case of parental instinct gone haywire because it has no baby to lavish its attention on. Encourage everybody to delay marriage and treat women as men-with-boobs, and it is any surprise that the craving for interaction with someone truly other manifests in more unusual ways?