Eugene Wigner, the physicist who noted the “unreasonable effectiveness of mathematics,” restricted his awe and wonder to its ability to describe the inanimate world. Mathematics proceeds according to its own internal logic, and so it’s striking that its conclusions apply to the physical universe; at the same time, how they play out varies more the further that we stray from physics. Math can help us shine a light on dark worlds, but we should look critically, always asking why the math is so effective, recognizing where it isn’t, and pushing on the places in between. In the nineties, David Roberts and Keith Paulsen sought only to model the physical motion of the gooey, shifting brain. We should proceed with extreme caution as we try to model the world of thought that lives there.