Because of the “all-or-none” character of nervous activity, neural events and the relations among them can be treated by means of propositional logic. It is found that the behavior of every net can be described in these terms, with the addition of more complicated logical means for nets containing circles; and that for any logical expression satisfying certain conditions, one can find a net behaving in the fashion it describes. It is shown that many particular choices among possible neurophysiological assumptions are equivalent, in the sense that for every net behaving under one assumption, there exists another net which behaves under the other and gives the same results, although perhaps not in the same time. Various applications of the calculus are discussed.
A more serious thing, in the reviewer’s opinion, is the complete absence of contributions dealing with information theory and the central nervous system, which may be the field par excellence for the use of such a theory. Although no explicit reference to information theory is made in the well-known paper of W. McCulloch and W. Pitts (1943), the connection is quite obvious. This is made explicit in the systematic elaboration of the McCulloch-Pitts’ approach by J. von Neumann (1952). In his interesting book J. T. Culbertson (1950) discussed possible neural mechanisms for recognition of visual patterns, and particularly investigated the problems of how greatly a pattern may be deformed without ceasing to be recognizable. The connection between this problem and the problem of distortion in the theory of information is obvious. The work of Anatol Rapoport and his associates on random nets, and especially on their applications to rumor spread (see the series of papers which appeared in this Journal during the past four years), is also closely connected with problems of information theory.
Electronic copy available at: http://www.cse.chalmers.se/~coquand/AUTOMATA/mcp.pdf
