Aristotle’s On generation and corruption raises a vital question: how is mixture, or what we would now call chemical combination, possible? It also offers an outline of a solution to the problem and a set of criteria that a successful solution must meet. Understanding Aristotle’s solution and developing a viable peripatetic theory of chemical combination has been a source of controversy over the last two millennia. We describe seven criteria a peripatetic theory of mixture must satisfy: uniformity, recoverability, potentiality, equilibrium, (...) alteration, incompleteness, and the ability to distinguish mixture from generation, corruption, juxtaposition, augmentation, and alteration. After surveying the theories of Philoponus , Avicenna , Averroes , and John M. Cooper , we argue for the merits of Richard Rufus of Cornwall’s theory. Rufus was a little known scholastic philosopher who became a Franciscan theologian in 1238, after teaching Aristotelian natural philosophy as a secular master in Paris. Lecturing on Aristotle’s De generatione et corruptione, around the year 1235, he offered his students a solution to the problem of mixture that we believe satisfies Aristotle’s seven criteria.Author Keywords: Mixture; Mixt; Chemical combination; Accidental potential; Potential; Elements; Medieval chemistry; Peripatetic chemistry; Aristotelian science; Richardus Rufus; Averroes ; Avicenna ; Philoponus ; John M. Cooper. (shrink)

Aristotle’s On generation and corruption raises a vital question: how is mixture, or what we would now call chemical combination, possible? It also offers an outline of a solution to the problem and a set of criteria that a successful solution must meet. Understanding Aristotle’s solution and developing a viable peripatetic theory of chemical combination has been a source of controversy over the last two millennia. We describe seven criteria a peripatetic theory of mixture must satisfy: uniformity, recoverability, potentiality, equilibrium, (...) alteration, incompleteness, and the ability to distinguish mixture from generation, corruption, juxtaposition, augmentation, and alteration. After surveying the theories of Philoponus (d. 574), Avicenna(d. 1037), Averroes (d. 1198), and John M. Cooper (fl. circa2000), we argue for the merits of Richard Rufus of Cornwall’s theory. Rufus (fl. 1231–1256) was a little known scholastic philosopher who became a Franciscan theologian in 1238, after teaching Aristotelian natural philosophy as a secular master in Paris. Lecturing on Aristotle’s De generatione et corruptione, around the year 1235, he offered his students a solution to the problem of mixture that we believe satisfies Aristotle’s seven criteria. # 2004 Elsevier Ltd. All rights reserved. (shrink)

The bulk of Duhem's writing which bears on the understanding of mixtures suggests he adopted an Aristotelian position which he opposed only to the atomic view. A third view from antiquity-that of the Stoics-seems not to be taken into account. But his lines of thought are not always as explicit as could be wished. The Stoic view is considered here from a perspective which Duhem might well have adopted. This provides a background against which his somewhat unorthodox Aristotelianism might be (...) understood. (shrink)