There seems to be more dimensions to it though. Trivially, a dog and a human might be on one axis, but you can't rank differently intelligent humans along that

There seems to be more dimensions to it though. Trivially, a dog and a human might be on one axis, but you can't rank differently intelligent humans along that same axis. The average dog, while strictly and obviously not as intelligent as a human is not impaired, they function at their fullest. While as humans go further down and away from mainline human intelligence become obviously impaired. We seem to have a notion that intelligence has multiple dimensions to it, so it's more likely that human intelligence exists as some kind of probabilistic gradient on a hyperplane in a high-dimensional space, and sampling from that plane yields any possible human intelligence profile, while sampling away from that space yields something decidedly not human. Other animals thus must be similar hyperplanes, perhaps in their own space, and likely not intersecting with humans at all.