On the occasion of bis sixtieth birthday, we dedicate this volume to Jan Wo­ leriski-s-our teacher, our colleague, our friend. Both of us are particularly indebted to Jan not only with regards to profes­ sional matters, but some private ones as well. Hence, we hope that he forgives us an occasional lapse into fondness and affection. That said, may the list of bis personalmerits remain shrouded in mystery; rather than unveil them, we open here by appraising Jan's presence from a broader perspective. Tonote that Jan was not always a part of our lives would not evoke surprise. However, to imagine the Institute of Pbilosophy on Grodzka Street or Krakow pbilosophy without him in it would be a harder task-at least for us, Nonethe­ less, we do remember the days when he was commuting to Krakow as a guest lecturer. Is there anything about those days which particularly comes to mind? To shed light on the story which follows, one must begin by stating that the early 1980s when we were studying philosophy was not a bright period. The great masters of Krakow philosophy-Ingarden, Mehlberg, Zawirski, or Dambska-> were either dead or, for political reasons, kept silent. The years following Martial Law (1981-1983) were intellectually very blighted and barren. In the midst of all this we were attending Jan's course on general methodology.

Jaakko Hintikka is the author or co-author of thirty volumes and of some 300 scholarly articles in mathematical and philosophical logic, epistemology, language theory, philosophy of science, history of ideas and history of philosophy, including Aristotle, Descartes, Leibniz, Kant, Peirce, The Bloomsbury Group, Husserl and Wittgenstein. He has also been active in international scholarly organizations, most recently as the First Vice-President of FISP, Vice-President of IIP and Co-Chair of the American Organizing Committee of the Twentieth World Congress of Philosophy. He has been Editor-in-Chief of the International Journal Synthese and the Managing Editor of Synthese Library since 1965.