理論評価基準IFから情報の自然化を考える

Abstract

In the philosophy of information, the problems of how to categorize multiple notions of information and what properties should be given to each categorized notion of information are widely discussed. The problem of the nature of natural information --which is also important for the “naturalization of information”, an open problem in the philosophy of information-- is one of them. Various definitions of natural information have been proposed by F. Dretske and other theorists, and there is an ongoing debate over the only definition of “natural information”. In these circumstances, S. D'Alfonso devised the criterion for evaluating definitions of natural information : “Information Flow” (IF). According to him, this criterion is a collection of properties that it is desirable for a definition of natural information to satisfy, and by checking the degree to which these properties are satisfied, we can measure the quality of the definition of natural information. However, the validity of applying this criterion has not yet been sufficiently examined in preceding studies, and it is necessary to evaluate whether this criterion is functioning properly. Through clarifying what this criterion evaluates and how this criterion evaluates the object of its evaluation, this paper discusses the following two points; (1) With regard to the process of naturalizing information, which is one of the open problems, I shall clarify what we need to do to be one step closer to naturalizing information. This work allows us to regard the naturalization of information as a question of dividing it into two steps and then asking how we can bridge the gap between the two steps. (2) I shall reinforce the reason why we should consider natural information in a pluralistic way by dividing it into two types, “objective theory” and “doxastic theory, ” which have been considered in a monistic way in previous studies. This work allows us to see that the advocates of doxastic theory criticized Dretske's definition based on a misinterpretation of it.