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)

1. This paper addresses the development of mutual relations between two sets of ideas in scholastic logic. First, consider the following statements: (1) It is impossible to encounter a chimera.(2)...

The ArgumentIn this paper, I argue that the most significant contribution of the Jesuits to early modern science consists in the introduction of a new “image of knowledge.”In contradistinction to traditional Scholasticism, this image of knowledge allows for the possibility of a science of hypothetical entities.This problem became crucial in two specific areas. In astronomy, knowledge of mathematical entities of unclear ontological status was nevertheless proclaimed certain. In theology, God's knowledge of the future acts of man, logically considered as future (...) contingents, was also proclaimed certain. In both cases the concept of certain knowledge of hypothetical entities was problematic and challenged a central premise of the accepted canons of logic, i.e., that the objects of true knowledge must be real objects.The main argument of this paper is that the practical orientation of the Jesuit cultural milieu enabled Jesuit scientists and theologians to ignore accepted logical considerations and to modify traditional Thomist images of knowledge. Nevertheless, this modification was not so radical as to change the contemporary organization of knowledge. This was due to the peculiar status of the Jesuits within the church establishment, which exposed them to harsh criticism and created a deep need for legitimation. Thus, the limitations of Jesuit scientific culture are accounted for in institutional, rather than in logical terms. (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)