There's a dialogue in a Vernor Vinge book, between two self-aware entities within some very sophisticated computer. It goes something like:
AI 1: "We shouldn't be..."
AI 2: "Thinking this?"
AI 1: "No. Thinking at all."
That's how consciousness strikes me. It seems the human body and its behavior is mechanical from bicep down to the quark. We are a sophisticated bit of clockwork: so why this sense of awareness? When the body's behavior would be precisely the same without it? I shouldn't be thinking this--indeed, I shouldn't be thinking at all.
Yet I think. This awes me.
I learned of this topic a year ago, when I was reading the New York Times Book Review and came upon a nasty (and funny) exchange between Daniel Dennett and John Searle. Still cracks me up.