I offer an alternative account of the relationship of Hobbesian geometry to natural philosophy by arguing that mixed mathematics provided Hobbes with a model for thinking about it. In mixed mathematics, one may borrow causal principles from one science and use them in another science without there being a deductive relationship between those two sciences. Natural philosophy for Hobbes is mixed because an explanation may combine observations from experience (the ‘that’) with causal principles from geometry (the ‘why’). My argument shows (...) that Hobbesian natural philosophy relies upon suppositions that bodies plausibly behave according to these borrowed causal principles from geometry, acknowledging that bodies in the world may not actually behave this way. First, I consider Hobbes's relation to Aristotelian mixed mathematics and to Isaac Barrow's broadening of mixed mathematics in Mathematical Lectures (1683). I show that for Hobbes maker's knowledge from geometry provides the ‘why’ in mixed-mathematical explanations. Next, I examine two explanations from De corpore Part IV: (1) the explanation of sense in De corpore 25.1-2; and (2) the explanation of the swelling of parts of the body when they become warm in De corpore 27.3. In both explanations, I show Hobbes borrowing and citing geometrical principles and mixing these principles with appeals to experience. (shrink)

An introduction to Thomas Hobbes as a systematic and not merely political philosopher. Best known for his contributions to political philosophy, Thomas Hobbes set out to develop a coherent philosophical system extending from logic and natural philosophy to civil and religious philosophy. In this introduction to Hobbes’s thought, Otfried Höffe begins by providing an overview of the entire scope of his work, making clear its systematic character through analysis of his natural philosophy, his individual and social anthropology, and his political (...) thought. He then offers an innovative examination of religious and ecclesiastical questions, touching not only on the political implications of religion so important to Hobbes, but also on his attempt to reconstruct Christianity in terms of a materialistic philosophy. He also explores Hobbes’s continuous critique of Aristotle and Aristotelian Scholastics, in which Höffe argues that Hobbes and Aristotle have much more in common philosophically than is normally supposed—and certainly more than Hobbes himself acknowledged. Finally, Höffe sketches the influence Hobbes had and continues to have on the development of legal and political philosophy. “A thoroughly successful introduction to the philosophy of Thomas Hobbes ” — Reinhard Brandt, in Süddeutsche Zeitung, in praise of the German edition. (shrink)

Thomas Hobbes of Malmesbury, one of the greatest philosophers of law and state, died 250 years ago, on December 4, 1679. His name was so frequently associated with a certain unfortunate conception of his moral and political philosophy, that the public's lack of interest in this centenary is not to be wondered at. So far, even amongst the scholars who admitted his merits, few tried to penetrate into the depths of his thought, and only at the end of the last (...) century, thanks to the writings of Ferdinand Tönnies and George Croom Robertson, was a new impulse given to research into Hobbes’ spiritual heritage. A series of monographies was published, and the personality of Hobbes appeared in a new light. His theories, when better known, proved to be less crude and more human than they had seemed, for they are a reaction from the revolutionary tendencies of his time. (shrink)

Hobbes' philosophy of geometry was eccentric to contemporary movements and worsted in specific controversy. But he laid down stipulations defining geometry and its method which might provide a significant and workable alternative "meta-geometry". Some of these are isolated and reinterpreted here, especially those concerned with describing magnitudes, motions and quantities, and with his use of proportions. Rather than refutation of commentaries and historical rehash, the effort here is to isolate definitive texts and to offer a reinterpretation of their arguments in (...) succinct form showing their coherence and their interdependence with his other philosophic principles. (shrink)