Richard Rufus's theory of mixture: A medieval explanation of chemical combination

Annals of the New York Academy of Sciences

Volumn 988, Issue , 2003, Pages 282-292

  Weisberg, Michael ^a,b   Wood, Rega ^a  

^a STANFORD UNIVERSITY   (United States)

^b UNIVERSITY OF PENNSYLVANIA   (United States)

Author keywords

Accidental potential; Aristotelian science; Averroes; Combination; Elements; Medieval chemistry; Mixt; Mixture; Potential; Richard Rufus

Indexed keywords

BIOCHEMISTRY; CHEMICAL ANALYSIS; CHEMICAL COMPOSITION; CONFERENCE PAPER; LITERATURE; SCIENCE; THEORY;

ARISTOTELIA;

EID: 0038724160     PISSN: 00778923     EISSN: None     Source Type: Book Series    
DOI: 10.1111/j.1749-6632.2003.tb06109.x     Document Type: Conference Paper

References (32)

1. For a general discussion of Richard Rufus's life and work, the reader may wish to consult Rega Wood's article on Richard Rufus of Cornwall in Blackwell Companion to Philosophy in the Middle Ages. T.B. Noone and J. J.Gracia, Eds. Blackwell Publishers. Malden, MA. [in press]. Information about the Richard Rufus of Cornwall Edition can also be found at http://www.stanford.edu/~regawood/rufus/
2. MAIER, A. 1952. Die Struktur der materiellen Substanz. In An der Grenze von Scholastik und Naturwissenschaft, 2nd ed., pp. 88, 137-139. Rome.
3. NEEDHAM, P. Duhem's theory of mixture in the light of the Stoic challenge to the Aristotelian conception. In Studies in History and Philosophy of Science. In press.
4. ARISTOTLE. Metaphysics VIII.2.1043a13 and On Sense and Sensibilia III.440b1-3. [Editor's note: References to Aristotle's works are given according to Bekker's 1831 system, showing page number, column letter, and line number. This information is generally included as marginal notes to current published translations.]
5. ARISTOTLE. On Coming to Be and Passing Away 1.10.327a33-327b10. [Editor's note: This paper follows the practice of much current philosophical literature, and of the Forster translation, in using the English word "mixture" to translate the Greek μιξις (mixis). The Foster translation also uses "mixture" to render the Greek μικτος (mixtos) -for which this paper uses the antique English word "mixt." In contrast, the revised Oxford translation by H. H. Joachim (1984. The Complete Works of Aristotle. J. Barnes, Ed. Princeton University Press. Princeton, NJ) construes mixis (in On Coming to Be) by the English word "combination," and uses forms of the verb "to combine," rather than forms of "to mix." Most people familiar with the language used in contemporary chemical discourse would find the Joachim translation much more congenial than the Foster version. Michael Weisberg has pointed out that, in translating a passage in an earlier work of Aristotle (Topics 4.2, 122630, Barnes, ed., page 206), Joachim uses the English "mixture" for mixis (μειξις). (For the Greek text, see: Ross, D. 1974. Aristotles Topica et Sophistici Elenchi. Clarendon Press. Oxford.) In this passage, Aristotle contrasts mixis (μειξις) with krasis (κραςις), "blending" - pointing out that merely putting two components together (mixing) does not necessarily mean that those components will blend (combine). It seems that Aristotle's use of mixis (μειξις) in Topics is similar to the modern chemists' use of the English word "mixture" and quite different from his more technical use, in On Generation, of mixis (μιξις) to mean a homogeneous ("blended") combination. (In a preface to his translation of On Coming to Be, Foster comments on the difficulty of translating technical terms, and also has high praise for Joachim's work.)
6. ARISTOTLE, On Coming to Be, I.1.314a20 and I.10.328a10
7. ARISTOTLE, On Coming to Be, 1.10.328a25-30
8. ARISTOTLE, On Coming to Be, I.10.32762-27
9. ARISTOTLE, On Coming to Be, 1.10.327623-27
10. ARISTOTLE, On Coming to Be, I.10.32768
11. FINE, K. 1995. The problem of mixture. Pac. Philos. Q. 76: 266-369.
12. CODE, A. 1995 Potentiality in Aristotle's science and metaphysics. Pacific Philosophical Quarterly 76: 405-418; the forthcoming Symposium Aristotelicum for 1999, devoted to book 1 of On Coming to Be and Passing Away can be expected to continue the controversy. In press; ARISTOTLE, De generatione et corruptione I: Proceedings of the Symposium Aristotelicum, Deurne, 1999. Frans de Haas and Jaap Mansfeld, Eds. Oxford University Press. Oxford, UK.
13. DE HASS, F. 1999. Mixture in Philoponus: an encounter with a third kind of potentiality. In The Commentary Tradition on Aristotle's De generatione et corruptione. J. Thijssen and H. Braakhuis, Eds. Turnhout.
14. MAIER, Die Struktur, 3-140.
15. ARISTOTLE, On Coming to Be, I.10.328a33 and II.4.331a24
16. AVERROES. 1550. Aristotelis opera cum Averrois Cordubiensis commentariis 5, In De Caelo 3.67.ed. apud Junctas. Venice.
17. MAIER, Die Struktur, 38.
18. MAIER, Die Struktur, 38-39.
19. AVERROES,In De Caelo, 3.67.
20. MAIER, Die Struktur, 46.
21. Maier, of course, cannot be faulted for this mistake since the manuscript of Rufus's commentary on Aristotle's On Coming to Be was not known in her day. For more on the relationship between Rufus and Roger Bacon, see WOOD, R. 1997. Roger Bacon: Richard Rufus's successor as a Parisian physics professor. Vivarium 35: 222-250.
22. RICHARDUS RUFUS CORNUBIENSIS. In De generatione et corruptione Aristot. 2.4.2: "Sed dicendum quod aliquo modo est ibi remissio et intensio - ita, scilicet, ut dicamus intensionem in ipsa forma actu exsistente; remissionem autem in ipsa secundum potentiam exsistente, ut prius tactum est. Et a forma ignis actu exsistente causatur calidum intensum, et ab eadem potentia exsistente, mota tamen in parte ad actum, causatur calidum remissum. Sed tamen ipsa forma [lectio dubia E] substantialis secundum quod est sub ratione formae non suscipit intensionem et remissionem" (Q312.18ra). Quotations are based on a provisional edition of Rufus' works edited by R. Wood and N. Lewis. Since this edition is unpublished, citations are to the manuscripts at Erfurt University, Amploniana Quarto 312.
23. RUFUS, In De Gen 1.6.3: "Et in tali statu, ut mihi videtur, debemus ponere formas miscibilium in mixto, ita ut cum quaelibet possit de se exire in actum, quaelibet tamen per aliam prohibetur" (Q312.16vb-17ra).
24. RUFUS. Dissertatio in Metaph. Aristot. 9.4: "Sciendum est autem quod materia ultima est res naturalis, quae est necessitas cui impossibile est additio. Nihil enim [tamen E] tall materiae deficit nisi solum actualitas, et ilia [add. vero E] actualitas non addit essentiam aliam" (Q290.27vb).
25. RUFUS, In De Gen 1.6.3: "et cum est necessitas, tunc est in potentia accidentali et per se ipsam exiens in actum si non sit prohibita. Et in tali statu, ut mihi videtur, debemus ponere formas miscibilium in mixto" (Q312.16vb).
26. RUFUS, In De Gen 1.6.3: "Et antequam est necessitas, semper est forma in potentia essentiali et indiget agente" (Q312.16vb).
27. Of course unlike accidental potential, which has a very specific state attached to it, there are many ways for a form to be in essential potential. This is where the terms "near" and "remote potential" become useful. "Accidental potential" refers only to the state of lacking nothing but actuality. Forms that are in essential potential, however, can be near or far from becoming actual.
28. RUFUS. Memoriale in Metaph. Aristot. 7.16: "Dici potest quod miscibilia sunt in mixto actu incompleto et diminuto, et ita patet conclusio. Sed ut quaesita in parte ista pateant intellige quod miscibilia sunt in mixto non potentia essentiali nec in actu, sed in potentia accidentali sive secundum actum incompletum, non tamen violente, propter confusionem formarum suarum in naturam tertiam quae est forma mixti" (Q290.49va).
29. RUFUS, In De Gen 1.6.3: "Et in tali statu, ut mihi videtur, debemus ponere formas miscibilium in mixto, ita ut cum quaelibet possit de se exire in actum, quaelibet tamen per aliam prohibetur. Sic ergo non est ibi actu forma, nec tamen sola materia, sed potentia mota ad formam - ad quam potentiam, quia ipsa est natura formalis, consequitur virtus. Et sic etiam ad talem potentiam motam ad formam ignis, cum ex terra generatur ignis, consequitur caliditas in eadem materia adhuc exsistente sub forma terrae" (Q312.16vb-17ra).
30. RUFUS. In De Gen 2.4.3: "Consequenter potest dubitari sic: Si, sicut dictum est, miscibilia prout sunt in mixto sunt necessitates, ergo omnes mixtiones erunt similes, quia quod necessitas est completum est quantum potest citra actum" (Q312.18ra).
31. RUFUS. In De Gen 2.4.3: "Dicendum quod non sequitur hoc, quia sicut ignis, lux et flamma et carbo differunt aliquo modo secundum maius et minus, sic et necessitates ad ipsa. Et sic contingit potentiam aliquam, quae est necessitas, esse et secundum plus et secundum minus." (Q312.18ra).
32. RUFUS. In De Gen 2.4.3: "Possumus iterum dicere quod aliqua mixtio est sic, in qua unurn contrarium est sic in necessitate, alterum autem non, ut est in aliquo mixto quando est in corruptione. Et iuxta hoc possumus verificare hoc quod dicit Commentator, quod formae elementorum sunt media inter substantias et accidentia sive formas substantiales et accidentia,ut intelligamus hoc secundum quod sunt in mixtione. Sunt enim ibi ut potentiae et non in suis actibus ultimis, et in hoc deficiunt a forma substantiali simpliciter; eo autem quod simul coniunctae possunt perficere materiam, plus habent quam accidentia" (Q312.18ra).