• DYNAMICS OF REASON Stanford Kant Lectures The Stanford Kant Lectures are an invited series sponsored by the Stanford University department of philosophy. Philosophers are invited to reflect on the state ofthe art in their field and to report on current research in a way that is accessible to the broader community of scholars, educators, students and the public at large. Topics range from Kant's philosophy of science to the nature of human desire. The Kant Lecturer is selected by the department in light ofits judgment that the speaker has a deep understanding ofthe issues in his or her field, and a vision of their connection to questions of lasting con­ cern across academic disciplines. MICHAEL FRIEDMAN Dynamics ofReason The 1999 Kant Lectures at Stanford University CSLI Publications I C~nter for the Sludy of [illI• Language and Information SlaPlford, California Library ofCol1gress Catllioging-in-Pllblicatioll Data Friedman, Michael, 1947- Dynamics of reason / Michael Friedman. p. em. (Stanford Kant Lectures) Includes bibliographical references and index. ISBN 1-57586-291-3 (alk. paper)-lsBN 1-57586-292-1 (pbk.: alk. paper) 1. Science-Philosophy. 1. Title Q175 .F892 2001 SOl-dC21 2001017171 hi memory of Carl Gustav ("Peter") Hempel teacher, mentor, friend It might be supposed that [reason's demand for systematic unity and simplic­ ity1is merely an economical contrivance whereby reason seeks to save itselfall possible trouble, a hypothetical attempt, which, if it succeeds, will. through the unity thus attained, impart probability to the presumed principle of explanation. But such a selfish purpose can very easily be distinguished from the Idea. For in conformity with the Idea everyone presupposes that this unity of reason accords with nature itself, and that reason - although indeed unable to determine the limits ofthis unity - does not here beg but command. -Kant Contents Preface xi Part One: The Lectures I. The Idea ofa Scientific Philosophy 3 II. Historical Perspectives on the Stratification of Knowledge 25 III. Rationality, Revolution, and the Community of Inquiry 47 Part Two: Fruits ofDiscussion I. The Relativized A Priori 71 2. A Priori Principles and Empirical Evidence 83 3. Rationality and Revolution 93 4. The Role ofPhilosophy 105 5. Other Problems, Other Sciences 117 References 131 Index 137 ix Preface For the past twenty years I have been pursuing historical studies on the rela­ tionship between developments in scientific philosophy from Kant (in the late eighteenth century) to logical empiricism (in the early twentieth) and concurrent developments taking place within the sciences, principally within the exact sciences of logic, mathematics, and mathematical physics. These studies concentrated on Kant's involvement with the sciences of his time (Euclidean geometry and Newtonian physics, for example) and the various ways in which late nineteenth and early twentieth century revolutionary changes within these sciences (non-Euclidean geometry and relativistic phys­ ics, for example) motivated early twentieth century logical empiricists to undertake similarly revolutionary changes in the Kantian and neo-Kantian philosophy oftheir time. My primary aim was to depict the deep and intricate connections between the historical development of scientific philosophy, on the one hand, and the parallel evolution of the exact sciences themselves, on the other. I did not, however, attempt to draw substantive morals for our contempo­ rary philosophical predicament from these historical studies. Indeed, my dominant tone was rather unhopeful. Kant's original philosophical synthesis had failed due to unforeseen revolutionary changes within the sciences, and the logical empiricists's radical revision of this synthesis had also failed to do justice to the very rapid changes taking place within early twentieth century science. In response to this situation I offered only the indeterminate sugges­ tion that we, too, should attempt a fruitful interaction between contemporary philosophical practice and developments within the sciences themselves, and the pessimistic conclusion that we now have no idea how to go about this given the twin failures ofKantianism and logical empiricism. In the mid to late 1990S I began to see a way out ofthis dilemma. It was not yet clear how one could preserve any kind of commitment to a Kantian or xi xii Dynamics oJReason neo-Kantian conception of a priori principles in the exact sciences (as in Kant's original conception of the synthetic a priori, for example, or Rudolf Carnap's version of the analytic a priori developed in the logical empiricist tradition), but I was convinced, at the same time, that the dominant view­ point within contemporary scientific philosophy some or another version of naturalistic epistemological holism is entirely incapable of providing an adequate philosophical perspective on these sciences. The idea I then came up with, against this twofold background, was that one could attempt to com­ bine basic aspects of Carnap's philosophy of formal languages or linguistic frameworks with fundamental features of Thomas Kuhn's much less formal theory of scientific revolutions. And in this way, more specifically, one could articulate a conception of dynamical or relativized a priori principles within an historical account ofthe conceptual evolution ofthe sciences rather than a purely syntactic or semantic account of the formallanguage(s) of the sci­ ences. One could thus reap the benefits of Kuhnian conceptual history while simultaneously avoiding the drawbacks of Camapian formal Wissen­ schaftslogik. In particular, W. V. Quine's well-known and widely accepted attack on the Carnapian conception of analytic truth need no longer compel us to adopt a thoroughgoing epistemological holism according to which there is nothing left ofthe a priori at all. In 1997 I had the opportunity to deliver the Whitehead Lecture at Harvard University and the Presidential Address to the Central Division ofthe Ameri­ can Philosophical Association. I chose, for both occasions, the topic of "Philosophical Naturalism" [Friedman (1997a)], where my aim, in particular, was to attack the contemporary consensus in favor ofQuinean epistemologi­ cal holism on behalf of a neo-Kantian (and historicized) conception of relativized a priori principles. I found, at the same time, that I was thereby able to develop a new positive conception ofthe peculiar role ofscientific phi­ losophy vis-a.-vis the sciences, as a distinctive meta-scientific level ofthought or discourse making its own indispensable contribution to the rationality of radical conceptual revolutions (Kuhnian "paradigm-shifts") taking place within the sciences themselves. I further developed these ideas in a second paper, "On the Idea ofa Scientific Philosophy:' which I then delivered as part ofa series on "Science and Defining the Human" at Northwestern University, as the Stice Lecture at the University ofWashington, as a Distinguished Visitor at the University ofCalifornia at Riverside, as the Jacobson Lecture at the Uni­ versity of London, the Hall Lecture at the University of Iowa, and the Werkmeister Lecture at Florida State University. This last paper then became the first lecture in the three-lecture series that Preface xiii comprises Part One of the present volume. In the academic year 1998-99 I had the opportunity to deliver this three-lecture series on four different occa­ sions: as the Simon Lectures at the University ofToronto, as part ofmy annual visit to the University of Western Ontario, as the Hempel Lectures at Prince­ ton University, and as the Kant Lectures at Stanford University. I was especially pleased to have had the opportunity to present the Hempel Lec­ tures at Princeton, both because I had been a student of Hempel's at Princeton in the early 1970S and because my attempt at combining Kuhnian ideas with aspects of logical empiricism was complementary, in a way, to Hempel's own efforts to undertake a parallel accommodation in the later part of his philosophical career - beginning in the early 1970S and extending into the early 1990S [see, in particular, the essays from this period collected in Hempel (2000)]. Whereas Hempel had focussed on the kinship between the pragmatic and anti-formalistic dimensions of Kuhn's thought and Otto Neurath's naturalistic version of logical empiricism (by which Hempel him­ self had been significantly influenced during his early years in Berlin and Vienna), I was attempting to exploit the kinship between the Kuhnian notion ofscientific paradigm and the Carnapian notion oflinguistic framework so as to move scientific epistemology in a less pragmatically naturalistic and more Kantian direction. Finally, I had the opportunity to discuss the ideas of the three lectures at the Fifth Gottinger Philosophisches Kolloquium at the University of Gottin­ gen in June of 1999. In this colloquium series students in the Gottingen philosophical seminar study the work in progress of a particular philosopher during the academic year, followed by a three-day session at the end where papers on this work are presented by the students and intensively discussed with the philosopher in question. On this occasion I had provided the three lectures, together with related materials such as Friedman (1997a), (1997b), (1998), and (2000a). I am deeply indebted to the organizers of the collo­ quium, Felix MUhlholzer and Olaf Miiller, and, most especially, to the students who prepared papers on my work: Marita HUbner, Lorenz Kahler, Tobias Klauk,