In what dimension do you measure hight of thought? I guess on the one hand this could be linked to the architecture of the brain, directly translating to some topological notion. On the other hand, you might simply argue that others and self are on two different planes of existence and that higher consciousness is not concerned with just self and emotions, but with thoughts of thoughts ... per se, on very high levels of abstractions. And as those thought models are, if the bayesian crowd is to be any judge, highly probabilistic, those thoughts are just hypothetical. So, you are just saying they harbour wrong thoughts. They (we) are painfully aware of the possibility, but not very precisely. Then, in absence of other viable theories, they run with it.

In effect, I guess, if they have a low opinion of other creatures, they might not have a high opinion of themselves.