Late-scholastic and Cartesian conatus

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Acknowledgements

This paper could not have been written without the support of the Università degli Studi di Torino and the hospitality of the Max-Planck-Institut für Wissenschaftsgeschichte of Berlin: my first thanks goes to these institutions. I also desire to thank my supervisor, Enrico Pasini, Catherine Wilson, Massimo Mori, and Pietro D. Omodeo for reading and commenting on previous drafts of this paper. At the Institute I also had the opportunity to discuss this or closely related issues with Peter McLaughlin, Vincenzo De Risi, and Adam Chalmers: all of them deserve my thanks. Very useful comments also came from presenting this paper at the 2013 edition of the Bucharest-Princeton Seminar in Early Modern Philosophy. In particular, I desire to thank Dan Garber, Vlad Alexandrescu, Ofer Gal, Sophie Roux, Ohad Nachtomy, Sorana Corneanu, Andrea Sangiacomo, and Ian Lawson for the useful advices. Thanks also to the two anonymous readers for the useful comments. A special thanks goes to Balint Kekedi for the long discussion on the Cartesian conatus we had on a May morning in 2013 in Budapest (you were actually right!) Thanks also to Cameron Brown Rigo for his help in the editing of the text.

Notes

1. Descartes, Principles of Philosophy, 39, 240–1; Latin taken from Descartes, Principia Philosophiae, in Oeuvres, 63.

2. Descartes, Oeuvres, 112: “unusquisque satis magna vi recedere conetur a centro vorticis in quo gyratur: retinetur enim hinc inde ab aliis globulis circompositis, non aliter quam lapis a funda” (my translation).

3. In defining a body's motive tendency as “intrinsic”, I do not imply that for Descartes motion is a property of things. For, as I better show later, according to Descartes it depends on God's action only. However, there is no doubt that Descartes considers rectilinear motion as the kinetic state that a body has quantum in se est, that is, independently from any external constraint or hindrance. It is in this sense that I use the expression “intrinsic motive tendency” or equivalent variants.

4. See Gaukroger, Descartes's System of Natural Philosophy, 108.

5. In his book The Mechanization of Aristotelianism, Cees Leijenhorst connects Hobbes's conception of conatus with its use in late-Scholasticism: “Hobbes' reinterpretation of the Aristotelian concept of conatus is another expression of his ‘continental’ rejection of active forces and inner potentialities. Although rejecting the scholastic theory of gravity and free fall, he retained the concept of gravity as an inclination, a striving, or what the scholastics call a conatus. His only quibble concerned the way scholastics defined the term. According to Hobbes, conatus cannot be an intrinsic, non-kinematic principle by which bodies move themselves. In his mechanism, all physical action is local action. This, if conatus is indeed physical action, it must be motion. It cannot be a mere potentiality to move, as the scholastics had it. In Hobbes' view, conatus is not an appetite to move, but actually motion itself.” Leijenhorst, The Mechanisation of Aristotelianism, 196.

6. Aristotle, Physics, 10–21, in The Complete Works of Aristotle, 92.

7. For an account of the Scholastic theory of motion, see Maier, Studien Zur Naturphilosophie Der Spätscholastik.

8. Aquinas, Summa contra Gentiles, 2 http://www.corpusthomisticum.org/scg2046.html (accessed 24 May 2013): “Inest enim omnibus appetitus boni: cum bonum sit quod omnia appetunt, ut philosophi tradunt. Huiusmodi autem appetitus in his quidem quae cognitione carent, dicitur naturalis appetitus: sicut dicitur quod lapis appetit esse deorsum. In his autem quae cognitionem sensitivam habent, dicitur appetitus animalis, qui dividitur in concupiscibilem et irascibilem. In his vero quae intelligunt, dicitur appetitus intellectualis seu rationalis, qui est voluntas.”

9. Goclenius, Lexicon Philosophicum, 114: “Distinctio ambigae verbi naturae. Appetitus ὁμονύμω dicitur: In igne ad occupanda loca superiora:in ferro ad sui conjunctionem cum magnete: in planta ad humore sugendum: in equo ad Venerem: in homine ad beatitudinem.”

10. Ibid., 115: “qui dicitur quodammodo improprie appetitus,” “that is somewhat improperly called aid somewhat inappropriately appetite”, (my translation).

11. Ibid.: “in stirpe, quae attrahit & appetit alimentum absque sensu [ … ].”

12. Ibid.:“In inanimis, ut magnete”.

13. Buonamici, De Motu, 392:“Ergo appetitus definitio talis afferri poterit, inclinatio necessaria ex natura cuiusq. rei ad bonum sibi coveniens secundum naturam”.

14. See Vitelleschi, Lectiones R. P. Mutii Vitelleschi in octo libros.

15. Wallace, Prelude to Galileo, 116.

16. Conimbricenses, Commentari in Octo Libros, V.6, Explanatio, 202 (my translation): “quandoquidem lapis externa vi sursum propellitur, reluctatur ascensui eius forma naturali conatu, & impulsu, quod deorsum nititur; sed etiam aqua ab igne calefit, eius forma calefactioni active repugnat, per ingenitam ad frigus inclinationem, et quantum potest frigum suum active conservando, et in igne.”

17. Eustachius, Summa, P.3, P2, Q6, 121 (my translation): “Corpora gravia supra levia, aut graviora supra minus gravia ubicunque sint gravitant: similiter levia infra gravia, aut leviora infra minus levia levitant. Cujus assertionis veritas experientia constat: ubicunque enim gravia ponuntur, confestim superiorem locum levibus aut minus gravibus, si haec infra sint, deferuntur, quod non sit, nisi mutuo gravium descendentium, levium ascendentium conatu, qui gravitandi et levitandi actu nuncupantur.”

18. Buonamici, De motu, V.35, 503: “Ideo quod unumquodque suae neci resistit, quantum potest; tantum abest ut eo properet, ut nisi virtus moventis resistentiam mobilis superet nunquam moveatur; et nisi prevaleat facultas violans, in pristinum locum semper retrocedat; neque ullo modo conatum moventis adiuvat, sicut adjuvaret saxum, si magno impeto deiicerunt [ … ].”

19. See for instance Roux, “La Philosophie Naturelle,” 75–94, and Palmerino, “Two Jesuit Responses to Galileo's Science of Motion,” 181–227.

20. Fabri, Tractatus physicus, 417, (my translation): “Decimò, cum manus ſuſtinet aliquod pondus immobiliter, non producit in eo impetum.”

21. Ibid.: “Respondeo omnem impetum non esse frustrà, licèt careat motu, vt patet in ipso impetu innato, cuius duplex est effectum; scilicet grauitatio, & motus, vt aliàs iam indicauimus; similiter impetus productus à potentia motrice, [ … ] potest duplicem effectum; primus est motus; secundus est nisus seu conatus oppositus extrinseco motui; [ … ] enim innatus semper habet motum, nisi impediatur ab alio corpore [ … ].”

22. degli Angeli, Della Gravità, 10 (my translation): “Vna portione di quest'acqua, ò aria sia resa per qualche accidente vn pochino meno densa, e graue, sìche il suo conato al discendere ceda in parte; vederà, che subito sarà spinta in sù da quell'altr'aria, ò acqua, la quale essendo inalterata, conserua il medemo conato, il quale eccede quello della rarefatta. [ … ].”

23. Borelli, De motionibus naturalibus, (Cap. 1, supp. II, 11 ( my translation): “Secundo loco suppono vim, seù conatum, quo fluida nituntur sese vnire sphæræ terraqueæ, effici per lineas erectae ab superficiem horizontis. & hoc patet quia quodlibet graueis naturali instinctu conatur ad centrum terræ accedere via breuissima, igitur directio prædicti motus, seù conatus compressiuus efficietur per semidiametros eiusdem terræ, hæ verò erectae sunt ab superficiem horizontalem, quæ sphæricè ipsam terram comprehendit, igitur manifestum eſt quòd motus seù conatus compressiuus omnium partium fluidi per lineas ab horizontem perpendiculares efficitur.”

24. For instance, there is no mention of the conatus in Averroes (Aristotelis Libri Physicorum 8) Buridan (Subtilissimae Quaestiones Super Octo Physicorum Libros Aristotelis), Nicolaus Oresme (Nicolaus Oresmes Kommentar Zur Physik Des Aristoteles,) or Duns Scotus (In VIII. Libros Physicorum Aristotelis Expositio et Quaestiones.)

25. There is no explicit use of the concept in Toletus (Francisci Toleti Commentaria) nor in the Complutenses commentaries on Aristotle's Physics (Disputationes in Octo Libros Physicorum Aristotelis.)

26. For instance, there is no mention of this specific use of the concept in Borro (De Motu Grauium, & Leuium) in Cardano (Opus novum de proportionibus) Giovanni-Battista Benedetti (Diversarum Speculationum Mathematicarum), Galileo Galilei's De motu antiquiora, Giovanni Battista Baliani (De Motu Naturali Gravium Solidorum,) or Andreas van Berlicom (Elementorum de rervm natvralivm gravitate).

27. Descartes, Correspondence, 185.

28. Des Chene, “Descartes and the Natural Philosophy of the Coimbra Commentaries,” In Descartes's Natural Philosophy, edited by Stephen Gaukroger, John Schuster, and John Sutton, London: Routledge, 2000, 29: “Descartes mentions the commentaries of the Coimbrans only twice in his correspondence. In 1640, anticipating objections by the Jesuits to the Meditationes, and having some desire ‘to re-read a bit of their Philosophy’, he asks Mersenne to send him the names of the authors ‘whom they follow most closely’. Wondering whether anything new has appeared in the last twenty years, Descartes adds that he recalls ‘only the Coimbrans, Toletus, and Rubius'; he also remembers, but not by name, ‘a Chartreuse or Feuillant’ who wrote an abrégé of ‘the whole School Philosophy’. That author turned out to be Eustachius a Sancto Paulo, and it was to Eustachius' Summa quadripartita, which is indeed a greatly condensed compilation of other philosophers' works, that he eventually turned.”

29. Ariew, Descartes among the Scholastics, 43–4.

30. See Descartes, Correspondence, 232: “J'ay achepté la Philosophie du frere Eust. à sacto P., qui me semble le meilleur livre qui ait iamais esté fait en cette matiere; ie seray bien aise de sçavoir si l'autheur vit encore’ and ibid., 233: ‘Et mon desire est d’écrire par ordre tout un Cours de ma Philosophie en forme de Theses [ … ]; & au mesme livre, de faire imprimer un Course de la Philosophie Ordinaire, tel que peut estre celuy du Frere Eustache, avec mes Notes à la fin de chaque question, où iìadjousteray les diverses opinions des autres, & ce qu'on doit croire de toutes, & peut-estre ò la fin ie feray une comparaison de ces deux Philosophies.”

31. On this, see Van De Pitte, “Some of Descartes's Debts.”

32. Descartes, Oeuvres, 183.

33. Ibid., 36, 240.

34. Ibid., 35, 240–241.

35. However, Stephen Gaukroger (has underlined that there are at least two passages in which Descartes seems to admit circular inertia (Gaukroger, “The Foundational Role of Hydrostatics and Statics”, 60–1). Gaukroger attributes this apparent contradiction to a “structural ambiguity” of Descartes account of motion, due to the fact that “Descartes models his kinematics on statics, and particularly on hydrostatics.” (ibid. 62).

36. Descartes, Principles of Philosophy, 241; Latin from Oeuvres, 63.

37. The Cartesian concept of resistance has been regarded by scholars as intimately connected to that of conatus. Since the treatment of this connection goes beyond the goal of this paper, I limit myself to recall the account of resistance as active persistence provided by Dennis Des Chene. Accordingly, “In Descartes's thinking [ … ] persistence can be regarded under a negative or a positive aspect. Negative persistence is the permanence of a state in the absence of external causes. I will call this simply persistence. [ … ] Positive persistence is the permanence, or the tendency to permanence, of a state, in the face of external causes. This I will call resistance. Although Descartes's first law asserts only that a thing will persist, in his second and third laws it is clear that a thing will also resist certain kinds of external cause. Resistance [ … ] was construed by some authors to be passive, by others as active, or, more specifically, reactive. That ambiguity remains in Descartes's physics, and [ … ] its underground survival helps to explain why he formulated the rules of collision so as to created a marked asymmetry between motion and rest.(see Des Chene, Physiologia, 273–74)” Nevertheless, it is worthy to note that here in The World, differently from the Principles, the resistance is merely understood as the external constraint that prevents the actual rectilinear movement of the body (for instance, the sling for what concerns the stone or the corpuscles or the other parts of heaven for what concerns the corpuscles of the second element rotating around the centre of their vortex.)

38. Descartes, Le Monde, 146–7.

39. Ibid., 151 (emphasis added).

40. The meaning of the concept of force in Descartes is a point of contention among scholar. The dispute concerns in particular the relation between force and bodies. Indeed, some scholars (see for instance, Gueroult and Gabbey in Gaukroger, Descartes: Philosophy, Mathematics and Physics) have claimed that force is to be understood as an actual property contained in bodies, whereas others have seen it as a consequence of the action of God on matter. For instance, Daniel Garber claims that “the force Descartes appeals to in Law 3, and the tendency a body has to persevere in its state derive from God, from the immutable way in which he sustains the world he creates, in particular, from the way in which he sustains the body in motion in that world. In this way force is not in bodies themselves. (see Garber, “Descartes's Physics,” 320.)”

41. Descartes, Principles of Philosophy, 242.

42. Descartes, Oeuvres, 64: “Lapis A, in funda EA per circulum ABF rotatus, eo instanti, quo est in puncto A, determinatus quidem est ad motum versus aliquam partem, nempe secundam lineam rectam versus C, ita scilicet ut linea recta AC sit tangens circuli. Non autem fingi potest illum determinatum esse ad ullum motum curvum: etsi enim prius venerit ex L ad A per lineam curvam, nihil tamen istius curvitatis intelligi potest in eo remanere, dum est in puncto A. Hocque etiam experientia confirmatur, quia si tunc e funda egreditur, non perget moveri versus B, sed versus C. Ex quo sequitur, omne corpus quod circulariter movetur, perpetuo tendere ut recedat a centro circuli quem describit. (My translation).” NB The standard English edition of the Principles does not provide a full translation of the text. Therefore, I will supply my own translations from the Latin when it is necessary, providing the original passage in the notes.

43. See McLaughlin, “Force, Determination, and Impact,” 85–6.

44. Descartes, Principles of Philosophy, 248.

45. Descartes, The World, 59, (my italics).

46. Ibid., 59–61.

47. Ibid., 75, (my emphasis).

48. Ibid.

49. Descartes, Principles of Philosophy, 260.

50. Descartes, Oeuvres, 109 (my translation. Emphasis added).

51. Ibid., 111: “primo quidem temporis momento, quo iste canalis agetur in gyro circa centrum E, globulus A motu tantum tardissimo progredietur versus Y; sed secundo momento paulo celerius incedet: priorem enim vim retinebit, ac praeterea novam acquiret a novo conatu recedendi a centro E [ … ], (my translation).”

52. Ibid., 112: “ista tensio, a sola vi qua lapis recedere conatur a centro sui motus exorta, exhibet nobis istius vis quantitatem,” (my translation).

53. Descartes, Principles of Philosophy, 259; Descartes, Oeuvres, 108.