Abstract

Over fifty years ago, H.M. was treated for chronic epilepsy by a bilateral hippocampectomy. Among the lasting side effects of this treatment was that H.M. could no longer form certain types of long term memories, although he could form others. One of the many morals philosophers and psychologists have sometimes drawn from this sad case (and others) is that information about the brain can be used to guide theorizing about the mind. More specifically, it has been claimed that differences in the way in which psychological properties are realized in the brain can be used in the delimitation of distinct psychological properties. In this paper, we build on the Dimensioned theory of realization and a companion theory of multiple realization to argue that the discovery of differences in neurobiological realization do not by themselves lead to the splitting of psychological properties. Such differences in realizers could constitute unique realizations of distinct psychological types or multiple realizations of one psychological type. Whether one has unique realizations or multiple realizations—whether psychological properties are split or not—is not determined by the neuroscience alone, but by the psychological theory under examination. Thus, one might say that, in the splitting or non-splitting of properties, psychology enjoys a kind of autonomy from neuroscience.