Consciousness has always been treated interestingly. We assume we have it, but we don't know exactly what it is. We know what doesn't have it (anything that's not us), and seem to feel it somehow arises out of "complexity." All well and good, and it may be true. But what if consciousness is really just a figment of our imagination? A matter of degree? Maybe there is no fundamental difference between us and blister beetles.

An interesting article in this week's New York Times Sunday Review: Are We Really Conscious?