McGinnis. Provo, UT: Brigham Young University Press. Bobik, Joseph. 1988. Aquinas on Matter and Form and the Elements: A Translation and Interpretation of the de Principiis Naturae and the De Mixtione Elementorum of St. Thomas Aquinas. Notre Dame, IN: University of Notre Dame Press. 57 See Wood and Weisberg (2004). Cooper (2004) provides a defense of Aristotle's own account of mixture. 58 Gilson notes, with his usual penetration, on the real distinction in Scotus: "Toute son habitude de pensée [Scotus's], qui l'incline à la multiplication des moments dans l'analyse, lui fait en revanche éliminer du concret les distinctions réelles chaque fois qu'il peut les éviter. Nous en aurons des preuves, mais aucune plus décisive que sa doctrine du mixte" (1952, 471). 59 See a discussion of this inCross (1998, 43 sq.). Cross speaks of "the principle" that "it is not possible that change occurs without the production and/or destruction of an individual thing." Acknowledgements Research for this article was financed by the Fonds Wetenschappelijk Onderzoek Vlaanderen (FWO). I thank Erin Islo and Charles T. Wolfe for reviewing my English, and the anonymous readers for comments. 336 Lucian Petrescu Cooper, John M. 2004. "Two Notes on Aristotle on Mixtures." In Knowledge, Nature and the Good: Essays on Ancient Philosophy, 148–173. Princeton: Princeton University Press. Cross, Richard. 1998. The Physics of Duns Scotus: The Scientific Context of a Theological Vision. Oxford: Clarendon Press. D'Alverny, Marie Thérèse. 1961. "Avicenna latinus I." Archives d'Histoire doctrinale et littéraire du Moyen Âge 28: 284–288. De Haas, Frans A. J. 1999. "Mixture