It is very difficult to talk about consciouness without using concepts that reveal we assume we are conscious and self aware. But we do things all the time that involve lots of mental processing but no consciouness: driving a car, playing the piano, turning a double play...I could go on.

Whether or not consciousness exists, our behavior is dominated by the illusion that it does. This is probably due to the nature of language itself, by which we conceptualize abstractions. When we say something like "I think it is raining" what is the "it" that is doing the raining? You could just as easily ask "Who is the "I" that is doing the thinking?" We only include it because our grammar demands an object.

In fact, I think there may be a lot of clues about the nature of consciousness embedded in languages and open to the science of comparative linguistics. What is it that all languages, even those invented totally independently of each other, have in common? I bet there are clues there about how the mind works. Perhaps the brain is only hardware, and it is language that is the software. Without language, we would be just as smart, but our behavior would be indistinguishable from that of animals.