It all rests on what your definition of consciousness is. Philip: > But when I use the word consciousness, I simply mean experience: pleasure, pain, visual or

It all rests on what your definition of consciousness is. Philip: > But when I use the word consciousness, I simply mean experience: pleasure, pain, visual or auditory experience, et cetera. But that just kicks the can again. What is "experience"? What is pain versus pleasure? Ultimately we have to arrive at a reductionist definition that doesn't reference undefined terms. After many years of thinking about this problem, here's my best shot: Experience is equivalent to state change, e.g. the state change induced in a thermometer or a radio receiver due to stimuli. Consciousness is ultimately a system of modeling that is complex enough to have developed a model of itself, thus "realizing" that the system is separate from the environment that produces stimuli. Humans arrived at consciousness through evolving larger and larger brains whose main goal is to model the environment and behavior of other individuals in order to predict what will happen next, in order to make plans for survival. Panpsychism is then scientific, and perhaps inescapable, if we use these definitions. But, it doesn't mean that rocks and black holes are conscious. Only those things that undergo state change in response to stimuli and are complex enough to have models of themselves. There is no evidence that rocks have information-processing capabilities at all, and worms' brains are too small to have a model of themselves, however simplified.