Abstract
One of the many research projects of Jaakko Hintikka was entitled “Logical tools for human thinking and their history”. This is in fact an apt summary of the lifetime work of this master logician who developed several new methods and systems in mathematical and philosophical logic, among them distributive normal forms, model sets, possible-worlds semantics, epistemic logic, doxastic logic, inductive logic, semantic information, game-theoretical semantics, interrogative approach to inquiry, and independence-friendly logic. He applied them to study problems in philosophy of language, formal epistemology, and philosophy of science. He combined systematic work with novel interpretations of important historical figures like Aristotle, Leibniz, Kant, Peirce, and Wittgenstein. Hintikka was one of the most cited analytic philosophers, and he influenced logic and philosophy also as a successful teacher and the long-time editor of the journal Synthese.
