Pierre Gassendi's Philosophy and Science: Atomism for Empiricists (review)

In his Preface, Fisher writes: 'My focus is the epistemological and scientific element of Gassendi's thought and in particular the relation between his empiricism and atomism'. His discussion will be most fully understood by the philosopher of science, but despite some discrepancy between American and British idiom (one may note the frequent occurrence of the expression 'just in case' in the sense, apparently, of 'supposing only that'), the main lines of argument can be adequately followed by the ordinary historian of ideas. Fisher's own summaries and recapitulations are helpful and are drawn on here. A broad, if unstated, goal of Gassendi's work, which we can readily detect from his extensive quotations from, and lengthy interpretations of, past thinkers, is to address a variety of questions of metaphysics, epistemology and methodology against the backdrop of the grand sweep of Western thought. The present work offers a view of his thinking at least partly detached from the thinking of his contemporary fellow intellectual travellers, and broadened to take account of his treatment of ancient and medieval writers with whom he took himself to be 'conversing'. Such an expansive historical focus — on what given philosophers see as their contribution to the tradition — respects the wider historical intentions that they may have, and Gassendi expends much effort discussing the history of philosophical issues. This focus helps avoid the strict contextualist's error of merely pushing back a presentist (='synchronic'?) framework some hundreds of years. That project — most useful in the history of ideas — is aimed at an understanding that is primarily historical rather than one that is primarily philosophical. Some commentators interpret Gassendi's theory of empirical knowledge as primarily negative in orientation — anti-Aristotelian or anti-Cartesian — but it is best understood as a positive perspective, in which he fashions a reliabilist account of truth-criteria and epistemic warrant, and a probabilist account of viable empirical judgement—both on the basis of his physical account of perceptual belief. Along the way he uses elements of his theory in response to past and contemporary thinkers; the theory as a whole, however, is startlingly novel for the seventeenth century. The negative side of this theory leans in the direction of the classical Sceptics: we cannot be conclusively certain about, nor find ultimate truths among, empirical beliefs. But the positive side rejects Sceptical doubt about empirical knowledge in rather robust fashion: such knowledge is possible because we can identify a variety of strengths normally associated with many of our beliefs about appearances — notably, their reliability, approximation to the truth and degrees of likelihood. The core claim of Gassendi's constructive scepticist programme rests on the truth, or, at least, verisimilitude, of atomism. Fisher has made an exhaustive study of the relevant literature and his commentary is close and acute. He makes an important contribution to the understanding of a major seventeenth-century French thinker.