This stemmed from IGottheCottons' thread, and the question helped me come up with this theory: If the term capacity is even in the same idea as unlimited human ability(capacity referring to a limit, be it high or low it still implies a limit exists), that don't really fit. I think human brain capacity can be increased and decreased depending on usage although I think the ability to alter one's total capacity is very strongly based on the starting figures. As for my opinion, I'm a very very firm believer of human fallibility/imperfection. I think that there must not necessarily be a limit to human understanding, but more of a range. Think of it as a number line like this(the numbers representing theoretical info.): -10__________0__________10 Say this is just a piece of the infinite number line, right? I say that people can see parts of it. Different people see different numbers, different people see different ranges of numbers. For example, say I can only see the numbers 5 through 10, while person A can see -10 through -5. Am I smarter than he? No, just different. Although, say I can see from -10 to 10, and person A can see from -10 to 15, do we think similarly and perceive much of the same info.? Yes. Does that make him smarter than I? Yes. As for the original question, somebody could see numbers 50-100, maybe they could cure cancer, but theoretically couldn't write a proper sentence. While somebody who sees 0-50 could be the most street smart drug dealer you could ever imagine, or anything you want him to be, long as the ability and given activities/stimuli align with one's mental range of perception. And I'm not saying it's an exact science, although at the same time it is(with all the electrical impulses and whatnot going on in the human brain, surely different people have different electrical patterns. aka different thoughts etc.)