In On Generation and Corruption 1. 10 and 2. 7 Aristotle discusses mixing and mixtures. Recent scholars tend to read the two texts together, thus treating the production of homoeomers in GC 2. 7 as a process of mixing the material elements. I argue that the tendency to treat homoeomers as mixtures of material elements is incorrect: GC 1. 10 explains the mixing of bodies that have already been produced from the elements, whereas GC 2. 7 explains the processes that (...) produce compound bodies from simpler constituents. In GC 2. 7 only the primary contraries mix in the formation of a homoeomer: material elements cannot be constituents of mixtures for theoretical and physical reasons. This makes sense of the production of homoeomers in GC 2. 7 despite worries about mixing the material elements. For Aristotle, the production of homoeomers is simultaneously a process of mixing the primary contraries and generating the homoeomers from the destruction of material elements. (shrink)

This paper offers an interpretation of Aristotle’s treatment of the homoeomerous, or like-parted, bodies. I argue that they are liable to be far more complexly structured than is commonly supposed. While Aristotelian homoeomers have no intrinsic macrostructural properties, they are, in an important class of cases, essentially marked by the presence and absence of microstructural ones. As I show, these microstructural properties allow Aristotle to neatly demarcate the non-elemental homoeomers from the elements. That demarcation, in turn, helps to clarify Aristotle’s (...) conceptions of both homoeomery and what it is to be a bodily element. On Aristotle’s account, I argue, a homoeomerous body, as such, is divisible into at least one part that is the same specific kind as the whole. Elemental bodies are the limiting case. For Aristotle, an elemental body is only divisible into parts that are of the same specific kind as the whole. (shrink)

The difficulties often attributed to prime matter hold for all hylomorphic accounts of substantial change. If the substratum of substantial change actually persists through the change, then such change is merely another kind of accidental change. If the substratum does not persist, then substantial change is merely creation ex nihilo. Either way matter is an empty concept, explaining nothing. This conclusion follows from Aristotle’s homoeomerity principle, and attempts to evade this conclusion by relaxing the constraints Aristotle imposes on elementhood, generation, (...) and substrata all fail, and even the minimal constraints imposed by the Problem of Material Constitution are enough to generate the dilemma. -/- Aristotle resolves this dilemma in Physics I.9 by postulating pure potentiality-for-substance as the substratum of substantial change. Because the substratum persists, substantial change is not creation ex nihilo, but because it does not persist actually it is not a kind of accidental change. Aristotle uses this approach to solve the Problem of the Mixt and the Problem of Material Constitution without weakening his constraints on elementhood, generation, or substrata. This pure potentiality approach must be carefully distinguished from other ‘traditional’ or ‘prime matter’ views that posit some actuality for the substratum of substantial change, and it is best understood in light of the analogy found at Metaphysics Θ.6. Pure potentiality-for-substance can do the work needed in a substratum for substantial change because Aristotle is able to ground the identity, existence, and characterization of the substratum in the corrupting and generating substances rather than the substratum itself. (shrink)

This article explores the main aspects of Aristotle’s scientific method in Meteorology IV. Dispositional properties such as solidifiability or combustibility play a dominant role in Meteor. IV (a) in virtue of their central place in the generic division of homoeomers, based on successive differentiation and multiple differentiae, and (b) in virtue of their role in revealing otherwise undetectable characteristics of uniform materials (composition and physical structure). While Aristotle often starts with accounts of ingredients and their ratio (e.g., solids that contain (...) a significant amount of water are liquefiable), the natural direction of his investigation is from observations regarding dispositional properties and their manifestation to accounts of composition and microstructure. Such passages tend to be easily syllogizable, a feature that—along with the criteria that shape his method of division—argues, I believe, for the compatibility of Meteor. IV with Aristotle’s theory of scientific inquiry. The concluding sections of my article deal more succinctly with reputable opinions and final causation in Meteor. IV.1–11 and with the relation between this treatise and Aristotle’s biological corpus. (shrink)