On the legacy of W.S. McCulloch.

In this paper, we review McCulloch's legacy, from his early work in neurophysiology, and its relationship to his philosophical quest for an 'experimental epistemology' to his role in the cybernetics movement during the 1940s and 1950s and his contributions to the development of computer science and communication theory. There are three parts in chronological sequence. First, the period up to his work at Yale University with Dusser de Barenne, where he concentrated on the experimental study of the functional organization of sensory cortex. Second, the time of his Psychiatric Chair at the University of Chicago and the organization of the Macy Foundation Conferences. To this period corresponds the genesis and publication of the most influential and quoted work by McCulloch and Pitts: A Logical Calculus of the Ideas Immanent in Neurons Activity. Third, the period of his research activity at the Massachussetts Institute of Technology where he, Lettvin, Maturana and Pitts produced epochmaking papers on epistemological neurophysiology, the modelling of the reticular formation and other work with da Fonseca and Moreno-Díaz. We finally refer to the International Conference that took place in McCulloch's memory at the 25th anniversary of his death. Our main conclusion is that McCulloch's writings are still a source of inspiration from neurophysiology to artificial intelligence and robotics.