Perhaps we should now define our terms very carefully, I am using the word consciousness to refer to the state of having a subjective experience. So states with

Perhaps we should now define our terms very carefully, I am using the word consciousness to refer to the state of having a subjective experience. So states without a subjective experience-- sleep or anesthesia or death-- are unconscious. Do you disagree? It's not at all clear to me that you can have subjective experiences while you are asleep. Usually dreams are considered a subjective experience and this is interpreted to mean that you experience a dream, and upon waking you remember that experience. But consider this alternative hypothesis: There is random brain activity during sleep, but no subjective experience of it. Upon awakening, the brain has to make sense of this nonsense activity and shoves it all into memory. This is, in a way, a "false memory". Thus you wake up and "remember" a dream that you did not experience.