I think we are saying similar things, but I'm getting the sense that you don't think there is a single unified theory to be found (not simply that humans are incapable of understanding it). Do you have a particular reason for thinking this?
Well, a unified theory should "explain everything", but not necessarily on the right level. For instance, basic undergraduate-level physics and chemistry are sufficient to explain both "why is copper a conductor?" and "why do dogs like steak?" but this is not the correct level of explanation that you'd go to in order to understand both these phenomena. To explain the conductivity of copper, you'll want to go to crystal structures and electronic energy levels, whereas to explain why dogs like steak you'll want to bypass all the chemistry and go straight to the fact that dogs are omnivores, that fresh meat is a large portion of their ancestors' diets, that animals have nervous systems programmed to keep them alive, that eating is necessary to stay alive, and so forth. You could conceptually go all the way down to "this atom likes that atom" but these aren't the principles which you'd reach for.
Similarly, while everything should in theory be explicable by the fundamental physics of the universe, it may well be that consciousness can arise purely from classical physics.
Well, a unified theory should "explain everything", but not necessarily on the right level. For instance, basic undergraduate-level physics and chemistry are sufficient to explain both "why is copper a conductor?" and "why do dogs like steak?" but this is not the correct level of explanation that you'd go to in order to understand both these phenomena. To explain the conductivity of copper, you'll want to go to crystal structures and electronic energy levels, whereas to explain why dogs like steak you'll want to bypass all the chemistry and go straight to the fact that dogs are omnivores, that fresh meat is a large portion of their ancestors' diets, that animals have nervous systems programmed to keep them alive, that eating is necessary to stay alive, and so forth. You could conceptually go all the way down to "this atom likes that atom" but these aren't the principles which you'd reach for.
Similarly, while everything should in theory be explicable by the fundamental physics of the universe, it may well be that consciousness can arise purely from classical physics.