I'd love it if well-informed nonphilosophers participated along with the philosophers. — Unseen
My current understanding of consciousness is a work in progress (read: crazyism), but it draws from process philosophy and integrated information theory. I’m in the process of trying to formulate it in ways that might eventually make it testable, but I think I’m a long way off, so I’ll just outline the basic idea, and we can go from there...
A rock lacks consciousness as described,
however each molecule in that rock has the capacity to receive some
information about its environment - even if that environment consists only of other rock molecules - as well as the capacity to respond to that information. If I pick up a rock from the riverbed and hold it in my hand, the molecules on its surface will respond to a change in temperature, causing a change in adjacent molecules, until the entire rock has responded (only not
as a rock). If I break that rock with a hammer, each molecule will respond to the vibration of the impact, but certain rock molecules will also ‘experience’ a change in environment, new information, and respond accordingly (oxidation, etc).
Does this mean a rock molecule is conscious? Not in the sense of having experiences, because it could only ever be vaguely aware of a momentary interaction with ‘more’. It has nothing to relate each piece of new information to except the sense of this/here/now that constituted its entire universe. This is what I refer to as one-dimensional awareness. Each interaction is a momentary and unrelated transfer of information from one molecule to the next. Anything non-living has one-dimensional awareness.
Most animals have developed a two-dimensional awareness: they can relate these momentary interactions to each other, and use the information they receive to make sense of their environment in terms of space (in front, behind, above, below, etc) and time, as well as other sense data. This awareness is a matter of distinction - they can prefer certain stimuli based on memory and respond accordingly, but not define or evaluate possibilities at this level. There is no self awareness at this level.
Humans (and higher animals) have gone on to develop a three-dimensional awareness: they can relate these interactions and the wealth of information they offer to each other and to previous scenarios, and determine a sense of ‘value’ in spacetime. They can develop the capacity to define, quantify, measure and evaluate the ‘best’ of possible responses (based on past experiences and detailed sense data) for future reference. Self awareness occurs at this level, but I would argue that this has created certain problems (eg. a flawed evolution theory).
There is a four-dimensional awareness, too. Humans have developed the capacity to relate these detailed interactions to each other, to all their previous experiences,
and to the experiences of others as communicated to them through various means. This enables us to make sense of the universe well beyond our own existence in spacetime, to empathise with others, understand our place in history, imagine possible worlds, get creative or suggest an explanation for consciousness.
There may very well be further dimensions...