Anthropomorphic intelligence
The world of Eithalica includes several species which possess what might be called “anthropomorphic intelligence;” that is, they can think and communicate rationally like humans can in real life.
Note on Terminology
Many authors have used different words for this: “sentience,” “self-awareness,” “sapience,” etc.
This is because humanlike thought and related phenomena are a subject of philosophy, and are impossible to collectively define without resting on assumptions that come from the author’s worldview—whether the author is aware of those assumptions or not. Any definition is therefore guaranteed to be plagued with problems and limitations, and fail to please everyone.
As humans we know that, whether by kind or degree, there is something that sets apart our cognition, moral agency, etc. from that of all other life on earth, but we don’t know (or can’t agree) what that something is. And whatever it is, in real life there’s no evidence that any other natural creature has ever shared it, either on earth or elsewhere.
If we see humanlike features on a cartoon animal (e.g. opposable thumbs, front-facing binocular vision, upright bipedalism, etc.) we readily describe this as a case of entertainment-driven anthropomorphism: the act of portraying a non-human creature or object with human features. Our capacity for rational thought is even more unique than any of those traits, so why should we treat it with less ownership? So far as we know, it’s as exclusive to us as if it were an identifying “fingerprint” of humanness.
As applied to aliens
Furthermore when we imagine it in extraterrestrials, our own experience of rational thought is the only source to draw from. Therefore, at heart this cannot be anything other than a projection of ourselves—just like when we imagine a cartoon animal that walks upright and talks. On the scale of world history, imagining such a thing at all is sort of a modern development. In any case, it's a process clearly fraught with anthropomorphic bias.
Many assume that our apparent uniqueness is a mere illusion born from lack of data, i.e. that we simply don’t know what aliens are like because we haven’t encountered them yet, but may at some time in the future. Some carry this expectancy to an almost absurd level of imminence, unfazed by the continual seep of disappointment they induce. If they ever get their wish, this would be an ideological cataclysm that would certainly justify updating the contents of this article.
Until then, many try to compensate for our anthropomorphic bias by imagining aliens as increasingly foreign and inhuman. They end up picturing Lovecraftian grotesquery, or godlike Kardashev beings, all of which in the end ring hollow and shallow against the creative oasis of anthropomorphism.
So we find that anthropomorphic bias is something to neither blunder past, nor fight against. Instead, we choose to acknowledge it here in this out-of-story way, and we accept the role of extraterrestrials in science fiction (including the ones in Eithalica) as mere entertainment devices that fundamentally cannot provide a satisfying treatment of the subject.