Sounds ridiculous that our pre-linguistic ancestors would not have conscious experiences of colors, sounds, dreams, etc just because they couldn't put them into symbolic form. Seems like a case of putting the cart before the horse. Language is relatively recent. The parts of the brain correlated with consciousness are older.
Yeah the theory seems to only explain interiority of our consciousness. But if I recall the author does seem to cover critiques like this in the first chapter where he explains what he sees as erroneous ideas about what consciousness is.
He give the example of automatized actions and the lack of conscious recognition of what would normally be experiences with conscious perceptions. For example driving, you often do not consciously feel the petals, or see a lot of the road you are obviously responding too.
I definitely do not buy the theory totally explains consciousness but the book makes a convincing enough case to not dismiss.
