Ask yourself this question: Am I conscious now? The answer is probably yes, but what does that really mean? What exactly is consciousness? Where does it come from? Are we always conscious, even when we don’t stop and recognize it? The quandary of consciousness has long puzzled scientists, psychiatrists, philosophers, and others, and numerous ways of explaining it have been proposed. Thursday, the writer Susan Blackmore joins us to explore some those theories as we probe the nature of consciousness.