How is it possible for me to be conscious of myself? How can a molecule in my brain or foot or whatever feel that it exists? I assume anyone would agree that an atom is not self-conscious, that neither is a rock or a cell or an insect... a baby human? Yet it seems, somewhere along the line of increasing brain capacity one becomes self-conscious. How is it that when a system such as myself becomes complex enough it becomes self-conscious? If we assume that a unit, one thing, can only be conscious of other things, is it that somehow we are many things conscious of each other, who mistakenly think of themselves as one thing. Is self-consciousness just an emergent property? Is it an illusion? These are extremely important questions for me as I think so much hinges on self-consciousness: the concept of soul/spirit and mind-body duality, free will, death.........

To the question 'how' corresponds some sort of scientific description of the phenomenon - and many scientists are indeed engaged in trying to understand 'how' the human brain has developed, indeed evolved, the sort of consciousness that enables us to ask questions about ourselves in the first place, what you call "self-consciousness". The work being conducted on that front is importand and you might find it illuminating. But there remains the sense that, by asking the question, we are reaching the very edge of our consciousness, beyond which nothing seems very familiar anymore. Science describes the physical, familiar world; it does not address the sense of unfathomability that arises out of our consciousness of what we do not understand. The "explanatory gap" mentioned by David Papineau above is the gap between the answers we can come up with, within our familiar, physical territory, and the persistence of the question beyond the scientific answer. We tend to reduce reality to our answers - for...