It's not so much ""the theory that physical matter is the only reality" as it is ""the theory that physical matter is the only reality for which we have good reason to believe exists".
Nobody disputes the existence of matter, energy, space or time (I should hope), the dispute is over whether or not there exist other types of things, such as "immaterial minds" or "spirits" etc. I've never seen either evidence for such other things nor any case that has established their necessity.
Nobody disputes the existence of matter, energy, space or time (I should hope), the dispute is over whether or not there exist other types of things, such as "immaterial minds" or "spirits" etc. I've never seen either evidence for such other things nor any case that has established their necessity.
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