Given that the mind is the brain, as materialists insist, those who would understand the mind must understand the brain. Assuming
that arrays of neural firing frequencies are highly salient aspects of brain information processing (the vector functional
account), four hurdles to an understanding of the brain are identified and inspected: indeterminacy, micro-specificity, chaos,
and openness.
My thanks to the editor of this issue and an unnamed referee for many pointed comments and helpful suggestions.