David Mermin points out a “bad habit” that afflicts most humans: mistaking a computational idealization for the real world. That would probably not be intellectually fatal. What can lead to brain damage is to take the real world to be an approximation of the ideal, rather than doing the reverse.

We talk about geometric shapes such as lines, circles, and spheres. Each of these words conjures up a picture of a perfect line, circle, or sphere. We know that no real line is perfectly straight and no circle can be made without imperfections, however minute. Yet our mental image is of the perfect geometric shape.

So it is easier in most cases for the mind to grasp the ideal rather than the real. Perhaps Nature is punishing us for our bad habit, forcing us to keep burning up CPU time without getting to the end of π. Not falling prey to the bad habit Mermin so beautifully discusses would clear up a lot of smoky haze in the intellectual environment.