> Is the human thought process parallel? For _my capacities_, I have the > impression that I'm more multitask than parallel. And context switch is > expensive because there is not only explicit data, but also implicit and > I'm not able, if I'm really doing something involved, to restore the > previous state without much ado.
I, for one, think that this analogy is incorrect. It is your perception of what the brain is doing (higher order functions) that appears to be sequential, however, underneath it all, the brain is being highly parallel at doing all the functions that keep us alive: basic motor functions such as breathing, eyesight (which in itself is a highly parallel endeavour), hunger, circadian rhythms if you will. Even the neocortex is parallel: you can easily talk while, say, navigating the corridors of a building. The fact that most tasks that require extreme concentration (and using several of our neocortex functions in a coordinated fashion to solve a single problem) appear, to us, to be dealt with by 'multitasking', may simply be an evolutionary shortcoming to be fixed in later generations. Something like being able to SMS at 40 words per minute while headbanging at a concert :) So, in essence, I think the brain may be exactly what Dijkstra had in mind in the earlier quote: its workings are so implicitly parallel that the word 'parallel' carries no meaning when describing it.
