"I'm not so sure that it's reasonable to say that if something "only" exists in the minds of a large network of humans, then it is not real." What is the mind?

"I'm not so sure that it's reasonable to say that if something "only" exists in the minds of a large network of humans, then it is not real." What is the mind? What are its boundaries? Does the mind only exist in the brain or as an epiphenomenon of the brain? Many scientifically-minded people think so, and it's often an unstated assumption among them, but it's an open and highly debatable subject among philosophers, as is the question of what is reality, what are human beings, and so on -- questions again, that many people consider settled and decided in favor of a materialist/physicalist, internal/external, dualist viewpoint. But for many philosophers it's not so clear, and many people in this world have a very different world view, where the boundaries of the mind extend beyond the individual, where people have non-material souls, where spirit being exist, where (for some religions) the individual is (in some sense) god, or at least has something divine in them, where lives are predetermined or perhaps directed from outside by some entity (like god or the devil), etc, etc... These sorts of accounts are usually dismissed by the scientific-minded, or (even more commonly) not even given any sort of consideration or acknowledgement, yet they are quite common among huge portion of humanity (including some scientists, who themselves can be and often are believers in one or more of such "unscientific" beliefs about the mind, humanity, or reality). So, what is really going on? I don't pretend to know, but I consider it far from a settled question, and suspect if there is any single, stable "truth" about the world, it's much stranger than any "scientific" explanation currently in fashion. Psychedelics tend to put such questions right in front of one's nose, front and center, as they pull the rug of certainty out from under the most dogmatic of us as we realize we're not in Kansas any more. This I consider one of the potentially most valuable psychedelic effects, if it can be greeted with openness, wonder and curiosity, instead of closing down, running away, or doubling down on dogmatic certainty.