Dissolving the Explanatory Gap: Neurobiological Differences Between Phenomenal and Propositional Knowledge

Abstract

The explanatory gap and theknowledge argument are rooted in the conflationof propositional and phenomenal knowledge. Thebasic knowledge argument is based on theconsideration that ``physical information'' aboutthe nervous system is unable to provide theknowledge of a ``color experience'' (Jackson,1982). The implication is that physicalism isincomplete or false because it leaves somethingunexplained. The problem with Jackson'sargument is that physical information has theform of highly symbolic propositional knowledgewhereas phenomenal knowledge consists in innateneurophysiological processes. In addition totheir fundamental epistemological differences,clinical, anatomical, pathological and brainimaging studies demonstrate that phenomenal andpropositional knowledge are fundamentallydifferent neurobiological processes. Propositional knowledge is phylogeneticallynew, highly symbolic, culturally acquired,exclusively human and expressible in differentnatural and artificial languages. By contrast,phenomenal knowledge (i.e.: knowingwhat-it-is-like to see a color) consists inqualitative experiences and phenomenal conceptsthat provide an internal, language-independentreference to the properties of objects and theneeds of the organism. Language andpropositional knowledge are exclusively humanattributes implemented in specific regions ofthe dominant hemisphere. This contrastssharply with the phylogenicallysensory areas that are common to animals andhumans, which implement qualitativeexperiences. Experiences are hard-wiredneurobiological processes that can neither betransmitted nor re-created through thesymbolism of propositions. Thus, I concludethat the fallacy in the explanatory gap and inthe knowledge argument is a fallacy ofequivocation that results from ignoringfundamental neurobiological differences betweenphenomenal and propositional knowledge.