The capacity of matter to primitively manifest to itself, as a way of existing independent of abstract description and human conceptions (i.e., mental and cultural activity), doesn't entail that it has the cognitive abilities of a brain (memory-based identification, understanding, guided goals, intelligence/creativity). The latter is contingent on a complex organization that isn't present in 99.9999... percent of the universe. It's a classification error committed by philosophy of mind to label an ontological characteristic or ability (manifestation) as a psychological property (i.e.,
panpsychism).
Put another way: No one can actually confirm that "not even nothingness" follows death, or that being the way non-neural matter normally exists to itself. Such a "just so" dogmatic story certainly doesn't facilitate explaining the phantasmal content of consciousness (images, sounds, odors, bodily sensations, etc), if matter has zero presentation of itself as anything. But it's certainly consistent with the evidence to assert that there is no working biological or technological apparatus available for recognizing and validating that there are chaotic, elemental phenomenal occurrences after death. Vaguely akin to a person claiming that they never dream, but the actual likelihood is that they simply don't retain memories of their dreams after waking up (ergo, the conviction that there was only blankness or missing time rather than "something").
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