The central theme of this book is that the intentional aspects of mental processes are explicable, with mathematics, as due to the operation of purely material brain mechanisms. Nelson's version of mechanism holds that "a being has a mind if and only if its body or certain bodily parts are guided by formally distinct rules of a complexity to account for intentionality, and it is capable of conscious feeling". But he limits his inquiry to an investigation of the first of (...) these two conditions only: "So far as I can see, mechanism as such has nothing whatever to say about the relationship between physical states and states of awareness such as pains and ideas, although it does specifically address itself to the understanding of cognition, intelligence, and other such attributes of mind". (shrink)