As a Franciscan friar, student, teacher, philosopher, theologian, and political theorist, William of Ockham was and remains one of the most stimulating thinkers of the Middle Ages. The one consistent characteristic of his professional output—both as a student and later as an opponent of papal authoritarianism—was the provocative nature of his ideas. In required commentaries on standard theological texts as well as in his later, more independently inspired treatises, Ockham demonstrated a genuine talent for suggesting and sustaining a number of (...) original, unorthodox and, occasionally, even outrageous ideas. Accordingly, Ockham holds the distinction of being the most rejected but influential philosopher-theologian of the fourteenth century, an observation that applies to his views on causality in which, for example, Ockham held the principle of action at a distance in order to save the causal account of some phenomena. One of the more interesting distinctions that he made, however, occurs in his treatment of sacramental theology as part of his account of God's causal activity with respect to the sacraments. (shrink)

Drawing on a half century of scholarship, of Polish studies of Copernicus and Cracow University, and of Copernicus's sources, this book offers a comprehensive re-evaluation of Copernicus's achievement, and explains his commitment to the ...

Pierre Duhem rejected unambiguously the strong version of realism that he believed was held by Copernicus. In fact, although Copernicus believed that his theory was clearly superior to Ptolemy's, he seems to have recognized that his theory was at best only approximately true. Accordingly, he recognized that his arguments were not demonstrative in the traditional sense but probable and persuasive. Duhem regarded even the belief in probably true explanations as misguided. Nevertheless, Duhem recognized that, even if metaphysical intuition does not (...) enter into the content of physical theories, the rejection of hypotheses could be explained only by appeal to common sense. Hence, Duhem held a qualified instrumentalism according to which physical theories are not realist, but the terms of ordinary experience and empirical laws are realist. Accordingly, Duhem rejected the complete subordination of science to philosophy as well as the complete separation of science from philosophy. Duhem's history of cosmological doctrines reflects his belief in the origin of the subordination of science to philosophy and of the struggle to achieve the proper balance without being driven to the opposite extreme of their complete separation. (shrink)

ArgumentLudwik Antoni Birkenmajer, following along the paths pioneered by Leopold Prowe, Maximilian Curtze, Franz Hipler, and J. L. E. Dreyer, joined them as trailblazers of Copernican scholarship in the nineteenth century. Educated in the classics and mathematics, Birkenmajer began by examining more closely the Cracow background to Copernicus's development and studying his works and annotations in books he owned or read. Birkenmajer contributed many discoveries that eventually became common knowledge, and his studies loomed over Polish research on Copernicus into the (...) 1970s. Focusing on historical context and his original insights, the essay reminds readers of his contributions, relates them to discussions of Copernicus's precursors, to the debate about Maragha precedents, his reading of theUppsala Notebook, and his account of the origin of Copernicus's heliocentrism. By means of a more critical assessment of his interpretation, the essay revises earlier accounts, rescuing the original insights that mark Birkenmajer's most important contributions to current debates and his efforts to reconstruct Copernicus's path to heliocentrism. (shrink)

In their commentaries on Peter of Spain’s texts, two professors at the University of Cracow, John of Glogovia and Michael of Biestrzykowa, provided interpretations of consequences and conditional propositions which either rejected the paradoxes of strict implication or placed on them such restrictions as to challenge traditional views about the relation between antecedent and consequent. Nicholas Copernicus may have been inflenced by those discussions.

The astronomical traditions on which Copernicus drew for his major works have been well researched. Questions about Copernicus's arguments and his education in logic have been less thoroughly treated. The arguments supplied by Copernicus in his major works are shown to rely to a large extent on well-known dialectical topics or inference warrants. Some peculiar features of his arguments, however, point to sources at Cracow that very likely inspired him to construct arguments based on the requirement of real connections between (...) antecedents and consequents as a condition for the validity of hypothetical conditionals. (shrink)

This article summarizes Ockham's interpretation of Aristotle's categories, showing how his account of connotative concepts introduced a revision in the Aristotelian doctrine about the relation between mathematics and physics. The article shows that Ockham's account influenced William of Heytesbury, John Dumbleton, and Nicholas Oresme to re-interpret disciplinary relations and disciplinary boundaries. They did so, however, in ways compatible with other basic principles of Aristotelian philosophy of nature; nevertheless, their modifications of the Aristotelian account of mathematics stimulated later philosophers to construct (...) robust theories of mathematics compatible with modern mathematical physics. (shrink)