This paper presents Duns Scotus's theory of mixture in the context of medieval discussions over Aristotle's theory of mixed bodies. It revisits the accounts of mixture given by Avicenna, Averroes, and Thomas Aquinas, before presenting Scotus's account as a reaction to Averroes. It argues that Duns Scotus rejected the Aristotelian theory of mixture altogether and that his account went contrary to the entire Latin tradition. Scotus denies that mixts arise out of the four classical elements and he maintains that both the elemental forms and the elemental qualities are lost in the mixture. Consequently, he denies the distinction between the process of mixture and that of substantial change through generation and corruption. The reassessment of Scotus's account modifies the current historical representation of this discussion, inherited from Anneliese Maier.Late medieval philosophers expended a great amount of effort on Aristotle's theory of mixture and developed various accounts of how mixts arise out of the four Greek classical elements.1 John Duns Scotus held a radical set of theses on the theory of mixture: that the elements are not kept in the mixts neither with respect to their form, nor with respect to their qualities; 2 that a single element can give rise to a mixt; 3 that mixts are not generated through the mutual action of the elements; and that they cannot be generated out of the four elements at all. 4 Consequently, he rejected Aristotle's theory of mixture as a process distinct from generation, 1 Following a common practice in the literature, I use the old English word "mixt" for the result of the mixture, mixtum, and "mixture" for the process, mixtio. The current English sense of mixture, which is closer to Aristotle's synthesis, a juxtaposition of elements (or its result), will not be used. 2 "Ideo est alia opinio, quam teneo, quod formae elementares non manent in mixto secundum suas essentias, nec eorum qualitates" (Lect. II, d. 15, q. un., 26). 3 "Similiter ex uno elemento generatur mixtum" (Lect. II, d. 15, q. un., 29). 4 "Credo autem quod nunquam mixtum generatur ex quattuor elementis mutuo agentibus" (Lect. II, d. 15, q. un., 30). "Ideo dico quod nunquam est necesse quod genereretur mixtum ex quatuor elementis concurrentibus, etiamsi concurrant per virtutem divinam, vel qualitercumque, nunquam ex eis generatur mixtum" (Rep. 2A, d. 15, q. un., 6).