In his review of my Prelude to Galileo, Ernan McMullin rejects my emendation of Pierre Duhem's “continuity thesis” wherein I develop the case for a pronounced medieval-scholastic influence on Galileo's science based on parallels between Galileo's early Latin compositions and lectures given by contemporary Jesuits at the Collegio Romano. He does so on two grounds: that the evidence of derivation I provide, using textual parallels, is so strong that it refutes the claim for any intellectual influence, being a better instance (...) of mindless copying than one of personal appropriation; and that, in any event, the logical structure of the argument which I attribute to Galileo's mature work is not that of demonstration ex suppositione as understood by Aquinas, and so the example I provide of Galileo's use of suppositio “does not link him in any significant way to the specifically Thomist tradition of natural science”. An adequate reply to this critique would require the introduction of more historical evidence than would be appropriate for the pages of this journal. A few remarks, however, may be in order concerning such evidence which bears directly on McMullin's first ground, and concerning the implications of this evidence for contemporary philosophy of science, which bear on his second. (shrink)

Peter Anstey has suggested that in our analyses of early modern natural philosophy we should abandon a frequently used distinction: that between rationalism and empiricism. He argues that we should replace it with another distinction, that between experimental and speculative natural philosophy. The second distinction, he argues, was not only widely used at the time, but has a greater explanatory range. It follows, he suggests, that it is a better way of “carving up” the writings of that period.It is clear (...) that a distinction between experimental and speculative natural philosophy did become common in the late seventeenth-century. But I am less convinced that it is a useful one. This.. (shrink)

: Although Galileo's struggle to mathematize the study of nature is well known and oft discussed, less discussed is the form this struggle takes in relation to Galileo's first new science, the science of the second day of the Discorsi. This essay argues that Galileo's first science ought to be understood as the science of matter—not, as it is usually understood, the science of the strength of materials. This understanding sheds light on the convoluted structure of the Discorsi's first day. (...) It suggests that the day's meandering discussions of the continuum, infinity, the vacuum, and condensation and rarefaction establish that a formal treatment of the "eternal and necessary" properties of matter is possible; i.e., that matter as such can be considered mathematically. This would have been a necessary, and indeed revolutionary, preliminary to the mathematical science of the second day because matter itself was thought in the Aristotelian tradition to be responsible for the departure of natural bodies from the unchanging and thus mathematizable character of abstract objects. In addition, the first day establishes that when considered physically, these properties account for matter's force of cohesion and resistance to fracture. This essay closes by showing that this dual style of reasoning accords with the conceptual structure of mixed mathematics. (shrink)