It seems really alien to our current mental metaphysical model, but if you study the subject and analyze the arguments, it's not as absurd as it seems. It's important to realize that when philosophers use the word "conscious" they don't generally mean "awake" or "aware" in a human-sense; virtually no one is positing that a rock is conscious in the same way a human being is.
Perhaps the main reason why panpsychism fell out of favor among philosophers and philosophers of science in the last century is due to the increased popularity of positivism and the linguistic turn. I'm not sure if panpsychism is necessarily a path forward in terms of describing the universe, but I think it seems promising in terms of a prescriptive use of creating, or attempting to create, new consciousness with machines.
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