Dualism is the belief that life forms are somehow bifurcated between body and mind, with an interface between the two. Therein lay the problem. Throughout history, despite relentless investigation, not even a scintilla of evidence for an interface between body and mind has ever been found. The mind-body problem has proved unsolvable.
“Even though everybody agrees that mind has something to do with the brain, there is still no general agreement on the exact nature of this relationship.” ~ Finnish psychologists Antti Revonsuo and Matti Kamppinen
The root issue of the mind-body problem is trying to entangle a duality; how do two very distinctive phenomena intimately interrelate?
“If this dualistic theory were true, it would confront us with the most embarrassing, insoluble difficulties should we try to explain how these two utterly different substances could interact with one another, as they appear to do in human behavior.” ~ American philosopher Mortimer Adler
If duality is an illusion, the mind-body problem dissolves. Either the brain manufactures the mind, or the mind fabricates a material mirage.
“Knowledge that a thing is false is a truth.” ~ German philosopher Arthur Schopenhauer