Chapter 10 picks up the various threads and defends the main thesis of the book (Methodological Mechanism), namely, the claim that to be committed to mechanism is to adopt a certain methodological postulate, that is, to look for causal pathways for the phenomena of interest. We compare our view of Methodological Mechanism with an important discussion by Joseph Henry Woodger concerning the meaning of mechanism, which has been ignored in current discussions, as well as with the views of Robert Brandon. We then formulate a dilemma that new mechanists face, which arises from the unstable combination of two main tenets of New Mechanism, an ontological and a methodological, both of which depend on the general characterisation of mechanism but that pull in opposite directions. We argue that Causal Mechanism is able to resolve the dilemma, by providing the best defence of the methodological tenet of New Mechanism, while at the same time preventing the adoption of a robust version of the ontological tenet.

Chapter 1 examines the relationship between Old and New Mechanism and uses it to illuminate the relations between metaphysical and methodological conceptions of mechanism. This historical examination will directly motivate our new deflationary account of mechanism developed in the subsequent chapters. We start by focusing on the role of mechanistic explanation in seventeenth-century scientific practice, by discussing the views of René Descartes, Christiaan Huygens, Gottfried Wilhelm Leibniz and Robert Boyle, and the attempted mechanical explanations of gravity by Descartes and Ηuygens. We thereby illustrate how the metaphysics of Old Mechanism constrained scientific explanation. We then turn our attention to Isaac Newton’s critique of mechanism. The key point is that Newton introduced a new methodology that freed scientific explanation from the metaphysical constraints of the older mechanical philosophy. Last, we draw analogies between Newton’s critique of Old Mechanism and our critique of New Mechanism. The main point is that causal explanation in the sciences is legitimate even if we bracket the issue of the metaphysics of mechanisms.

The Introduction recounts the main aspects of the recent revival of the mechanical philosophy and outlines the main theses of the book (i.e., Causal Mechanism and Methodological Mechanism). It presents briefly the case for understanding mechanism as a methodological concept, introduces the main concepts and distinctions that will be discussed in the book, provides an outline of the central arguments and presents a summary of the chapters.