Consciousness is what the body is doing to be viable.
Without it we can't walk, eat, reproduce, or do anything. I like to think cost viability reasons explain consciousness. I know people prefer metaphysical or quantum magic explanations, I prefer a prosaic one - cost. It's a mechanism to keep our costs offset by gains. Cost can also explain unity - we die as one organism, not each organ on its own.
Without it we can't walk, eat, reproduce, or do anything. I like to think cost viability reasons explain consciousness. I know people prefer metaphysical or quantum magic explanations, I prefer a prosaic one - cost. It's a mechanism to keep our costs offset by gains. Cost can also explain unity - we die as one organism, not each organ on its own.