I'm a smart guy, but the stronger I get the more I see muscle as the solution in place of brains. I used to feel good when I thought of a brilliant way to solve a problem, but now I get a bigger smile when I figure out how to challenge myself physically instead.
Perfect example was this week, my hot water pipe burst and I had a large flood. During the cleanup I had to rip out the walls and insulation, but the best part was the wood floor. It was damaged and curled so it needed to come up. Rather than do it the "smart" way I got a good grip and deadlifted sections up. It felt great, the fact that it was stapled to the plywood made it harder but more enjoyable as it gave in to me and my limited tools.
So perhaps I'm no dumber, but where I get satisfaction from sure is changing.