Descartes said that the mind and the body were two distinctly different substances. We LDS folk, of course, believe that our purpose for coming to Earth was to gain a physical body. We believe that our intelligence have always existed, but that the Plan of Salvation is required for us to obtain physical bodies. I'll equate the mind with the spirit, as that means most logical from an LDS perspective.
So, this leads me to the mind/body problem. How does the mind/spirit control the body? If we need bodies (which are physical) to influence physical matter, then how is it that we are able to control our bodies in the first place? How is it that a spirit can influence a body directly, but no other physical substance?
My only explanation is really no explanation at all. I think that spiritual matter and physical matter co-exist but do not effect each other. Unless, of course, you have a portal from one realm into the next. That is to say, the body is the portal by which our spirits are capable of interacting with the physical world. Or, perhaps, our spirits do not possess any energy whatsoever, just will and purpose. Perhaps the physical world consists of energy and substance and the spiritual world consists only of awareness. Then, if you apply the spiritual to the physical, you have purposeful direction of energies and substances, rather than random chaos or latency. Think of a person lying completely still, then moving. What changed? Well, the energy and power needed to move was always there, but it had no will to move, and therefore didn't. Perhaps it is all part of our eternal mission: to bring order to chaos.
I'm not sure if any of this made sense. I'll have to read this again tomorrow and see if I'm out of my gourde or what.