The word dimesional may not be a good choice, but the idea is to consider how many thoughts [maybe levels of awareness] we can carry at once. The other day while driving down a long, straight, remote road that passes through the grass fields, I was playing a little mental game to see how many things I could think of at once. Obviously this would normally be a bad thing to do while driving, but in my case there was absolutely nothing to hit, and no traffic. It seems that I could stay aware of my driving while [in my mind] singing along with the music on the radio, while adding two simple but different series of numbers. Beyond that I would start to lose track of my driving. I think Feynman did something like this and concluded that he could add five series of numbers simultaneously. Is this parallel processing, or do we just fool ourselves into thinking that we can carry more than one thought at a time? Can each of the minds that make up the brain carry an individual thought?