Glory & Weakness

I came home tonight very tired - and the only work I'd done had been sitting down for four hours. Editing this afternoon, but a little more frustrating than last time - a fair bit of effort for just a wee bit of result. I've found this can 'take it out' of one more efficiently than a hard days labour. You can push past incredible amounts of physical fatigue, but when mental fatigue sets in there's not a lot that you can do.
Which raises an old question: isn't mental tiredness a physical phenomenon? Do all our thoughts, emotions, memories, etc begin and end in the brain, or is our grey matter merely the facilitator of our mind and soul? Materialists hold that all thought is just the sum total of chemical reactions in our brain. If this theory is entertained though, we have no way of determining any truth or fact and we (including the materialists) could be as clueless in regard to reality as the The Matrix made us out to be. Those who believe that the body is primarily the dwelling place for a spirit are not bothered by such logic-bending concepts, but they have their own set of problems. By manipulating a persons brain it is possible to alter their choices, their emotions and yes, even their memories. If the spirit chooses, thinks and remembers then why is it so directly influenced by the brain? Again, I don't have the answers. I do believe (as stated in my last post) that humans are flesh and spirit combined, but I haven't the slightest clue how they interface. However I do think that the role of the body in making up our 'selves' has been downplayed by most religions, including Christianity. Maybe the Gnostics have left a mark on our faith after all. All matter is evil, they said. Only spirit is good. Bodies are to be despised, and the spirit exalted. No. Our bodies will expire, and therefore are not so important on the eternal scale. But while we have them, they are our glory and our weakness. Remember: angels long to see with our eyes.