Kosmic Konsciousness

I’ve been listening to Ken Wilber’s Kosmic Konsciousness on SoundsTrue the last couple of days, and am trying to sort out levels and lines.
This isn’t what he wanted me to get out of it at all.
It is my understanding that a spirit can be limited by the vessel it finds itself under some circumstances. It says something important about my unrealistic expectations that everyone can evolve. Some just can’t, they don’t have the proper structures for it. I just have to figure out exactly what that all means in terms of human potential. Can it be true that large numbers of humans don’t have the potential for enlightenment? When do we accept that we’ve gone as far as we can? Isn’t it a sort of surrender to settle into complacence, when we can’t know whether we’ve hit the glass ceiling, vs. whether we are merely at a plateau?
It also comes back to a previous conversation I had about animal intelligence. Some animals may happen to have brain structures that give them better reasoning skills, or the higher emotions, or perhaps an unusual capacity for understanding human language. Imagine owning a veritable Da Vinci among dogs. Would he get bored easily?
It convinces me all over again that intelligence is a continuum. All types, even the ones where I personally have severe deficiencies.
While humans are unmistakably at the top of the food chain, it is likely that there are animals that are more highly evolved in other lines. For instance, can you conceptualize a chair as a pattern of echoes rather than as a visual construct? Can you describe a chair by duplicating the sound reflections off that chair? Dolphins can and do. But they won’t be building any libraries any time soon.