The Logic of Cognitive Action

Human intelligence resides in our continually displayed cognitive skills, such as inference, learning, planning or searching, rather than in some static treasure house of accumulated knowledge. Hence, the logical structure of cognitive activities themselves is at least as important as that of their propositional or otherwise encoded products. This general epistemological view has a long philosophical pedigree dating back to the work of, amongst others, Wittgenstein, Popper and Toulmin, who have emphasized language games, learning strategies by trial and error, or juridical procedures as typical models for cognitive behaviour. Since the seventies, such dynamic views of cognition have found a more technical expression in philosophy and linguistics, witness various formal paradigms introduced by Hintikka, Stalnaker, Gardenfors, and the current "Dutch School" in dynamic logic. We shall discuss this movement, showing how both static and more dynamic aspects of cognition can be profitably studied from a logical point of view.