Wednesday, June 23, 2010

The Early Modern Theory of Heat: "Calor ut Octo"? Historians, Please Help!


As many of you know, I'm working on an English translation of Edouard Hugon's Cursus Philosophiae Thomisticae ("Thomistic  Philosophy Course"). I'm enjoying it immensely and I'm learning lots. But there is one passage with which I'm struggling; in particular, it's the expression "calor ut octo," which appears in a quote taken from John of St. Thomas, which is giving me trouble.  I have been able to figure out so far that it has to do with early-modern theories of the degrees of heat. I've consulted a number of reference works and experts on Thomistic thought, but I have nowhere found an explanation of this theory.  Doing a word study over some of the early modern Scholastics has led me to realize that each degree of heat is defined by some qualitative difference in the hot object (for example, if something is ignited, it is in the eight degree, but if it is just as warm as an animal's body, it is only in the first degree), and not by some quantitative difference (e.g., so many joules of kinetic energy, as we measure it today).  I have also come to the conclusion that "calor ut octo" should be translated as "heat in the eight degree."  Nonetheless, my curiosity has been aroused and I would like to learn more about the theory behind it.  So I'm throwing it out in the open hoping that some sage will illumine me, or at least that people who might have some knowledge  (or guess) on the topic can give me their two cents.

Here's the context of the expression "calor ut octo."  Speaking of the last disposition (ultima dispositio) that is required to be present in a subject for something new to be generated, Hugon points out that:

[...] Ultima dispositio procedit effective a forma genita et in novo composito recipitur, disponit tamen ad formam illam; unde posterior est forma in genere causae efficientis, prior vero in genere causae dispositivae et materialis.
Probatur. Accidentia sunt effective ab illa forma cujus sunt passiones et a qua dependent in esse. Atqui "ultima dispositio, v.g., calor ut octo, est accidens connexum cum forma ignis, ab illaque dependens in esse tanquam propria passio in ejus radice contenta, sicut clare videmus quod ignis genitus habet calorem ut octo tanquam proprietatem" (Joannes a S. Thoma, De generatione, q. I, art. VII).  Ergo ultima dispositio procedit effective a forma genita, et consequenter in novo composito suscipitur.

Here's what I have so far:

The last disposition proceeds from the generated form as from an efficient cause and is received in the new composite, but it is a disposition for that form; hence, the form is posterior in the genus of efficient cause, but it is prior in the genus of dispositive and material cause.
Proof. Accidents are proceed, as from an efficient cause, from the form of which they are passions and on which they depend in being (esse). But “the last disposition, e.g., heat in the eight degree is an accident connected with the form of fire, and is dependent upon that form in being (esse) as a proper passion contained in its root, as we clearly see that generated fire has heat in the eight degree as a property” (John of St Thomas, De generatione, q. I, art. VII).  Therefore, the last disposition proceeds effectively from the generated form, and consequently, it is received in the new composite.
Further, I did a word study of "gradus caloris" and "calor* ut" in a few early modern Scholastic authors, and I've found some interesting points:

-John of St. Thomas (1589-1644), author of the quote above, mentions in passing that:

(a) "calor ut octo includes many degrees," presumably all the other seven degrees. (Cursus philosophicus t. III, L. 4, C. 2: Sicut quia ad ignem requiritur calor ut octo tota illa dispositio per modum unius comparatur ad informationem formae ignis, licet calor ut octo plures gradus includat).

(b) "calor ut octo is in itself divisible but it is received indivisibly by the form of fire" (Ibid.: ... calor ut octo divisibilis est in se, et modo indivisibili respicitur a forma ignis).

(c) He also gives us an interesting explanation of how calor ut octo is transferred from an external object to our flesh and to our nerves.  (Cursus philosophicus t. III, L. 9, C. 7: "etiam calor ut octo potest sentiri, non solum qui est in ipso igne, sed qui communicatur carni antequam nervo. Communicatur autem carni comburendo illam, et sic cum incipit comburi, incipit quoque diffundi species caloris ut octo ad sensum et fit acerrimus dolor. Ut enim species transeat ad nervum, non requiritur, quod alteratio fiat in ipsomet nervo, sed sufficit, quod in ipsa carne ei coniuncta. In corporibus autem damnatis ignis applicatus carni sine alteratione physica et combustione speciem  caloris ut octo immittet in nervum, et praesertim quia ignis ille, ut diximus, etiam intra corpus ingredietur per poros.")

-The Salmanticenses (17th Century) imply that "calor ut octo" is the degree of heat needed for something to ignite (Cursus theologicus, T. 5, Tract. XIV, Q. 109).

-Cornelius a Lapide, SJ (1567-1637), the great biblical commentator, states that "all theologians hold with [St. Augustine], that the act or perfect contrition which includes the entire surrender of the heart to God, precedes, but at once brings with it justification and forgiveness of sin as its final result, in the same way as a certain amount of heat (calor ut octo) applied to wood, as a result produces actual fire in that wood."

-Francisco Suarez, SJ (1548-1617) is perhaps the most prolific on the subject:

(a) He states that calor ut octo is incompatible with water. (Disputatio XLV, Sectio II: "Et similiter calor ut octo videtur contrarius formae substantiali aquae, quam proinde expellit.")

(b) He speaks of different degrees of heat: calor ut unum, calor ut duo, calor ut tria, etc., calor usque ad quartum gradum, etc. (Ibid.: "Tertia ratio est quia, si tota forma mutaretur in intensione, impossibile esset alterationem esse continuam, quod infra probabimus esse falsum. Sequela patet, nam supponamus esse in subiecto calorem ut unum et intendi usque ad quartum gradum; si ergo calor ille, quando fit ut duo, amittitur omnino, et alius ut duo totus introducitur, et rursus, ut ille calor ut duo fiat ut tria, debet ipse expelli et alius perfectior introduci, interrogo quantum temporis duret in subiecto calor ut duo. Si enim duravit per aliquod tempus, ergo toto illo tempore cessavit alteratio, neque ultra processit, et ita non est continua intensio. Si vero duravit solum per instans, procedet ulterius argumentum ad gradum tertium; tunc enim impossibile est calorem ut tria durare tantum per instans, quia non dantur duo instantia immediata, et ideo necesse est quod duret per aliquod tempus intermedium inter duo instantia inceptionis et desitionis, in quo tempore non procedet intensio; nam, si procederet, iam corrumperet calorem ut tria ex dicta hypothesi; ergo impossibile est intensionem esse continuam, si in illa fit commutatio totius formae.)

(c) He questions the general view that the different degrees of heat are distinct qualities.  (Disputatio XLVI, Sectio I: [...] Et confirmatur ac explicatur; nam, si calor ut unum est qualitas indivisibilis, et similiter calor ut duo est etiam indivisibilis qualitas distincta a priori et perfectior illa eamque expellens a tali subiecto, et sic de caeteris gradibus, interrogo rursus an inter calorem ut unum et ut duo sit alia qualitas media perfectior quam calor ut unum et minus perfecta quam ut duo; idemque interrogandum erit in singulis gradibus, scilicet, an inter calorem ut duo et ut tria detur aliquod aliud medium, etc. Si enim non dantur aliae qualitates mediae, sed immediate fit transitus a prima qualitate, quae dicitur ut unum, ad secundam ut duo, et ab hac ad tertiam, et sic de aliis, evidens est alterationem non esse continuam, sed fieri quasi per tot saltus seu mutationes indivisibiles quot dicuntur esse gradus qualitatis, quia, cum omnes illae qualitates indivisibiles sint, ex natura rei indivisibiliter fiunt in eodem subiecto, et ideo fieri non possunt nisi per mutationes intrinsece indivisibiles, ex quibus non potest componi continua successio. Si autem inter qualitates primi et secundi gradus datur qualitas media, quaeram rursus an inter calorem ut unum et illam mediam qualitatem detur alia qualitas media [...]Tertio sequitur ex dicta sententia, calorem, verbi gratia, ut unum, sicut potest facere plures calores ut unum in diversis subiectis, ita in uno et eodem posse; et consequenter non solum posse facere aequalem calorem, sed etiam intensiorem se. Sequela pases, quia illi calores sunt eiusdem omnino rationis, et diversitas subiectorum accidentaria est agenti, dummodo in uno et eodem sit capacitas. Dices non sufficere capacitatem sine privatione et dissimilitudine passi ad agens. Postquam vero calidum ut unum fecit unum gradum caloris in passo, iam illud est simile agenti et non habet privationem talis caloris et ideo pati non potest ab illo agente. Sed hoc non satisfacit, quia passum illud habet privationem alterius gradus, alias a nullo agente posset illum recipere; ergo ex hac parte non impeditur actio.Dissimilitudo autem inter agens et patiens ideo necessaria est quia, si passum habet totam formam similem formae agentis, non potest aliam omnino similem recipere; si autem hoc posset, nulla esset ratio aut fundamentum cur illa conditio esset necessaria. Ergo in praesenti, si idem subiectum est capax plurium graduum caloris omnino similium, etiamsi unum habeat, et in illo iam sit simile agenti, non est cur illa similitudo ulteriorem actionem impediat; nam, quatenus alio simili gradu caret, est sufficienter dissimile ut illum possit recipere. Atque ita fit ut calidum ut unum possit efficere calorem ut duo, et consequenter ut octo, si aliunde non sit maior resistentia passi. Fit etiam consequenter ut duo calida ut unum possint se invicem augere in caloreetiam usque ad ignitionem quae consequitur ad calorem ut octo. Immo etiam sequitur quod idem calor ut unum possit ex vi solius caloris se intendere usque ad duos et tres et quoscumque gradus, ut patet applicando argumentum factum. Nam quod suppositum aut pars eius agat in se, non erit impedimentum, si aliunde supponitur (ut revera illa sententia supponit) idem subiectum secundum idem posse simul esse in actu formali respectu unius gradus et in potentia etiam formali ad alium gradum omnino similem.)

Any input would be appreciated!


Anonymous said...

It seems to refer to heat in its perfect form or as he says "ultimate disposition" (eighth degree) which is fire itself. Lesser degrees refer to lesser forms of heat or less perfect dispositions, like warm water, boiling water, the surface of an object just prior to combustion. Just guessing.

Anonymous said...

Its a long shot, but you might find something about this in "Methode de Nomenclature Chimique" written in 1787, published by Morveau in association with Lavoisier, Bertholet, and Fourcroy.