Argument (καθάπερ λέγουσί τινες) against mixture (μίξις) (327a35-b7):
(a) If the ingredients still exist and are not altered at all, they are no more mixed than they were before.
(b) If one ingredient is destroyed, then there is no mixture, because one ingredient exists while the other does not. For, mixture is composed of ingredients which remain what they were before.
(c) If both ingredients are destroyed, then there is no mixture. Based on the same reason as (b).
Aristotle's refutation (327b7-33)
(1) Mixture is not identical with changes in substance, quality, quantity or place.
(i) Mixture is not generation nor corruption: when wood burns, we do not say that wood has mixed with fire, although the fire comes to be and the wood passes away.
(ii) Nor is mixture the same as growth (D. Frede, 291): food is not said to mix with the body.
(iii) Nor is mixture alteration (291): when a lump of wax is formed, the shape is not said to mix with the wax. Nor can body and white be mixed. For, affections (τὰ πάθη) and states (τὰς ἕξεις) are not said to mix with their carriers (τοῖς πράγμασιν).
(2) The ingredients continue to exist in a mixture in a modified way. They do not remain in actuality what they were before they were mixed. Each of them retains but does not display its own potentiality.
Challenges (327b34-328a2)
(a) Are the ingredients said to be mixed when they are divided into very small particles and so set side by side with one another (παρ’ ἄλληλα) that each is not apparent to the sense-perception? [A popular view implied in the common use of the term mixture in every life.]
(b) Is every particle of one ingredient side by side with a particle of the other ingredient? [A view attributed to Democritus.]
Aristotle's response
(1) Mixture is not a matter of being perceptible or imperceptible. "A conglomerate of imperceptibles would not even fulfill the common-sense expectations of what it is to be a proper mixture." (293)
(2) "No kind of juxtaposition [sc. σύνθεσις] of parts can count as a mixture, no matter how fine the particles" (293) (brackets by me), since the ingredients of a proper mixture are homogeneous, just as any part of water is water, so any part of blended should be the same as the whole. τὸ μιχθὲν ὁμοιομερὲς εἶναι, καὶ ὥσπερ τοῦ ὕδατος τὸ μέρος ὕδωρ, οὕτω καὶ τοῦ κραθέντος. (328a10-12)
λεκτέον τοῦτο πῶς ἐνδέχεται γίνεσθαι πάλιν (328a17-18). A more Aristotelian account of mixture is in demand.
The Aristotelian account of mixture (328a18-31), i.e., the conditions of the occurrence of mixture (Joachim, 185: the proximate cause of the occurrence of mixture):
(1) (i) Some things, i.e., those whose matter is the same, are capable of acting upon and being acted upon. [Reciprocate Type] Mixture takes place in these things only.
(ii) Other things, i.e., those which do not have the same matter, are capable of only either acting upon or being acted upon. [Non-Reciprocate Type] Mixture does not take place in these things. For this reason, neither the art of healing nor health that is mixed with the patients' bodies can produce health.
(2) They are easily divisible (τοῦτο γὰρ ἦν τὸ εὐορίστῳ εἶναι, 328b2).
(3) There is some sort of balance between the potentialities (Ὅταν δὲ ταῖς δυνάμεσιν ἰσάζῃ πως, 328a28-29).
"Three conditions: sameness of genus, opposition of qualities, and overall equality in their respective powers" (D. Frede, 295).
It seems to me that sameness of genus and opposition of qualities refer to one and the same condition (1), as is summarized in 328b15-22 .
Case studies
(a) Neither the art of healing nor health that is mixed with the patients' bodies can produce health, since the art of healing and heal do not have the same matter as the patient.
(b) If one ingredient is a viscous liquid, it increases the volume and bulk, but otherwise produces no change.
(c) If one of the ingredients is (much) more susceptible (παθητικὸν) than the other, the result of the mixture is no great in volume or very little greater, but there is a change in color of the insusceptible ingredient.
Definition of Mixing (or Mixture)
ἡ δὲ μίξις τῶν μικτῶν ἀλλοιωθέντων ἕνωσις (328b22)
"Mixing is the union of the things mixed after they have been altered."
Problems/Observations
Is mixing a kind of mutual alteration of qualities, as the final definition suggests, and, if so, of what qualities?
What kind of unity of opposites is a mixture supposed to bring about?
Why does Aristotle not consider mixture as a subclass of substantial change, but instead regards it as a kind of quality change?
What kinds of qualities constitute mixtures?
What equilibrium between the ingredients does Aristotle have in mind?
In what way do the constituents of mixtures possess the same kind of matter?
References
Dorothea Frede, GC I.10: On Mixture and Mixables, Aristotle: On Generation and Corruption, Book I, ed. by Frans De Haas and Jaap Mansfeld, 2004
Harold Joachim, Aristotle On Coming-to-be and Passing-away, 1926
