I was born and grew up in Germany and though I have lived since then in the English-speaking world I remain considerably influenced by German culture and thought. Through an education in the classical languages I became interested early on in philosophy (both ancient Greek and German). I initially pursued that interest at the Universities of Bonn and Munich where I got to know something about modern logic, the philosophy of science, and the philosophy of language in the analytic tradition. Working with Oskar Becker, Wilhelm Britzlmayr, and Wolfgang Stegmüller, I read not only the work of Gottlob Frege and Rudolf Carnap but also the writings of Martin Heidegger. These early impressions left me convinced that the division between analytic and so-called Continental philosophy is artificial and I have never felt committed to taking sides in this sterile dispute.

I continued my philosophical studies at Oxford where I worked in particular with R. M. Hare, Gilbert Ryle, and Michael Dummett. It was also at Oxford where the influence of Wittgenstein, decisive for my thinking, first came to bear on me. Despite some public disagreements between Dummett and myself over the interpretation of Frege's work, I owe a great deal to him. I acquired from him, in particular, a constructivist view of logic and philosophy, but went beyond his overly abstract conception of what this comes by concluding that logical, mathematical, and philosophical concepts have to be understood as the concrete, temporal constructs of historically situated human beings. Dummett's intuitionism became thus for me the intellectual basis for an historicist approach to philosophy. Illustrations of that approach are found in my writings on Frege, Wittgenstein, Heidegger, and on German philosophy in the Nazi period.

After obtaining a B.Phil. at Oxford I taught for some years at University College London. I then moved to the University of California at Berkeley where I have been ever since. Having a restless mind, I have concerned myself over the years with a large variety of philosophical issues and authors. In addition to a continuing interest in early analytic philosophy (Frege, Russell, and the early Wittgenstein), I have more recently been thinking about human knowledge and, most actively, about issues in political philosophy. In my teaching I have been increasingly concerned also with the writings of Nietzsche, Heidegger, and Foucault. After many years of laboring, I feel that my work is only now beginning to come to fruition.