Hobbes, Descartes, and Ideas: A Secret Debate

Hobbes, Descartes, and Ideas: A Secret Debate GIANLUCA MORI* a key theme in the classical debate between Hobbes and Descartes, in the Third Objections and Replies to the Meditations, is that of the status of ideas.1 As has been observed, this question is at the center of at least six of the fifteen objections.2 But it is a debate that, officially, was soon over: Descartes did not enjoy this dialogue with a philosopher already suspected of heresy and, in March 1641, he begged Mersenne to break off all relations with “the Englishman” (he never called Hobbes by name).3 But such a break was foreign to Mersenne’s character: there was nothing he enjoyed better than intellectual polemics. And, over the following weeks, he continued to pass on to Descartes Hobbes’s objections against the Dioptrics, to which Descartes in any case never failed to reply, albeit unwillingly. Thus the debate on the Meditations was interwoven with that on scientific work, which had begun in late 1640. Descartes’s last reply to Hobbes is dated 21 April 1641 and is along the same lines as previous ones: if “the Englishman” is afraid of being defrauded of his philosophy he should publish it, but his most recent lines of reasoning “are just as bad as all the others of his that I have seen.”4 After which, apparently, silence fell on the debate. Thus Descartes, who trusted blindly in Mersenne, did not have the slightest suspicion when, barely a month later, the latter forwarded to him an anonymous letter in Latin on the very question of ideas, dated 19 May 1641.5 In his accompa1 Translated from the Italian by Frances Cooper. I would like to thank the anonymous referees for their insightful and stimulating remarks. 2 Marion, “Hobbes et Descartes,” 59–60. Hobbes’s Third Objections were certainly written after 24 December 1640 (Landucci, “Contributi,” 6); Descartes received them a few weeks later (see to Mersenne, 28 January 1641, AT III.293) and probably wrote his replies in February 1641, since in early March he was already at work on the Fourth Replies (see to Mersenne, 4 March 1641, AT III.330–31; and 21 April 1641, AT III.360–61). 3 Descartes to Mersenne, 4 March 1641: [L]e meilleur est que je n’aie point du tout de commerce avec lui (AT III.320). Hobbes was only named by Mersenne in 1646 (AT IV.736). 4 To Mersenne, 21 April 1641, AT III.354. 5 The letter was already to be found in the Clerselier edition (Lettres de M. Descartes, III.627–28) under the title “Objections métaphysiques,” then in AT III.375–77 as well as in Mersenne’s Correspondance, X.643–45. In this last edition, a gap in the text was noted and corrected (see AT III.874) but the correction proposed, though improving the sense of the passage, does not really amend it. * Gianluca Mori is Associate Professor in History of Modern Philosophy at the University of Eastern Piedmont, Vercelli, Italy. Journal of the History of Philosophy, vol. 50, no. 2 (2012) 197–212 [197] 198 journal of the history of philosophy 50:1 april 2012 nying letter, now lost, Mersenne probably did not give any hint as to the identity of the objector (which he obviously knew)6 so that Descartes, in his reply, could only refer to the May 19 letter as deux feuillets d’objections que vous m’avez envoyées.7 In later years and centuries, the author of the letter remained anonymous: most of Descartes’s many readers have given little importance to this short text, which occurs right in the middle of the great season of the Objections and Replies (to be precise, after he had written the Fourth Replies, to Arnauld, and at the same time as the Fifth Objections arrived from Gassendi).8 And yet it is this very letter—to which Descartes replied in two parts9—that brought a secret tail-piece to the debate opened by Hobbes with his Third Objections, and brusquely interrupted when it had barely started. The anonymous author, whose argumentative skill and philosophical acumen was initially appreciated, was indeed in all probability Hobbes himself, “the Englishman” whom Descartes so detested.10 The May 19 letter, addressed to Mersenne, begins with what might be simply an expedient: I have just read the Meditations, says Anonymous, but I have read them only once, and from this first reading some doubts have arisen that I would like to submit to Descartes. Is this a plausible statement? Suppose for a moment that Hobbes is writing this letter and that he wants to remain strictly anonymous, perhaps warned by Mersenne himself—who was not unfamiliar with, indeed was quite accustomed to this type of stratagem (the concealed author of the Second and Sixth Objections, Mersenne was about to launch his last attack on Descartes’s metaphysics under the disguise of “Hyperaspistes”).11 The close bond of friendship and collaboration between Mersenne and Hobbes is also well known: in 1642 Mersenne promoted the first edition of De cive, in Paris, and two years later he included one of Hobbes’s texts in a volume of his mathematical-scientific writings and used a summary of Hobbes’s thought as a preface to his Ballistics.12 Thus it would be entirely comprehensible that Hobbes should not have wanted to betray 6 In May 1641 the Meditations were still unpublished and the anonymous objector had read the manuscript copy that Mersenne had previously handed him (see AT III.375: Meditationes quarum copiam mihi fecisti). 7 AT III.382. 8 According to the editors of Mersenne’s Correspondance (X.643), the May 19 letter was sent on to Descartes together with the Fifth Objections, which left that same day; however, this is most improbable, because the letter was sent to Mersenne on May 19. One could even suppose that the date is fictitious and that Mersenne himself “concocted” the letter in its final version. Mersenne, initially, would have liked to include the anonymous objections within the future Sixth Objections that he himself prepared and sent in installments to Descartes during those weeks (see AT III.382); however, for unknown reasons, this was not the case. 9 See to Mersenne, 16 June 1641; July 1641 (AT III.382–83; 391–97). 10 See AT III.382: his objections were judged to be des meilleures et des plus fortes qui se puissent faire. Also Alquié noted the “depth” of a question posed in the May 19 letter (in Descartes, Œuvres philosophiques, II.347n3), but the only scholar—if I do not err—to have compared it with the Hobbes’s positions, from which he tried to distinguish it, was Aloyse-Raymond Ndiaye (La Philosophie d’Antoine Arnauld, 28–33); cf. also Nuchelmans, Judgment and Proposition, 132n45 and 132n43 (where the comparison remains indirect). Incidentally, but rightly, some authors have compared Descartes’s reply to the letter of May 19 with his reply to Hobbes: see Cottingham, “‘The Only Sure Sign…’,” 38; Ariew and Grene, “Ideas,” 89. But see also the first pages of Arnauld’s and Nicole’s La Logique, ou L’Art de penser, 41–46. 11 See Landucci, “Contributi,” 11–20. 12 See Lenoble, Mersenne, xxxviii. hobbes, descartes, and ideas 199 either himself or his friend and intermediary. This would fully explain why, in the letter, he presents himself as a completely new objector, eager to understand Descartes’s thought, but reluctant to come into the open. And in fact not even Descartes noticed the connection between the May 19 letter and Hobbes’s objections (to which we will of course return) and took the words of his unknown correspondent literally: “I imagine that this first letter is a sort of challenge thrown down to see how I will take it.”13 This is an instance of Descartes’s naivety that is not isolated within his intellectual biography: for example, on receiving the Second and Sixth Objections, he never even suspected that Mersenne himself was the author, despite Voet’s openly giving him away, and despite the various analogies with the objections that Mersenne had personally made to him from time to time.14 While failing to identify the author of the letter, however, Descartes was not unaware of its philosophical significance. In his second reply, he accused his anonymous adversary of reducing all knowledge to material imagination and thus (implicitly) denying the existence of a spiritual soul.15 He probably thought he was dealing with an adept of the Gassendist coterie in Paris (in fact, the same accusation of confusing intellect with imagination is to be found in Descartes’s replies to Gassendi’s and Mersenne’s objections).16 Be that as it may, once the courtesies were over, the May 19 letter came straight to the heart of the question, and that is to the meaning of the term ‘idea,’ that Anonymous took as his point of attack against the Meditations: I would like a clearer explanation, he says, (clarius mihi explicatum vellem) of what we should understand by this term, in particular when it is applied to the soul and to God. We should remember here that, at one point in the Third Objections, Hobbes had asked Descartes the same thing, that is to explain the idea of God better (melius explicare), and perhaps he had not been fully satisfied with the reply he received. Anonymous, for his part, starts from the definition of ‘idea’ given by philosophers—and in this case that means by the Scholastics (philosophorum vulgus). They consider the idea as a “phantasm,” that is, as the letter-writer interprets it, as an “image remaining … in the fancy” (imago manens … in phantasia). But already here, despite the apparent deference to tradition, we are quite close to Hobbes: the phantasm is indeed the chief protagonist of his entire epistemology, from his Short Tract and the first drafts of De corpore to the Third Objections and his correspondence with Mersenne and Descartes.17 More particularly, in the Elements of Law, the phantasm is defined 13 AT III.391. For Voet, see Descartes to Mersenne, 7 December 1642 (AT III.600). Clear analogies may be found between Mersenne’s letters and the Second and Sixth Objections, e.g. on the immortality of the soul (on which, in Meditations, there is pas un mot, AT III.366 = AT VII.127–28: [N]equidem verbulum); on the type of causality with which God creates the truths (in quo genere causae …, AT I.151 = AT VII.417–18); on the spontaneous generation caused by the sun and rain as an objection to the proof of the existence of God (AT III.274 = AT VII.123); on the fact that thoughts might only be des mouvements du corps (AT III.285 = AT VII.123: [M]otus corporei). 15 AT III.393: Mais j’appréhende qu’il ne soit de ceux qui croient ne pouvoir concevoir une chose, quand ils ne la peuvent imaginer, comme s’il n’y avait en nous que cette seule manière de penser et de concevoir. 16 See AT VII.139, 364. See also the reply to Hobbes’s Third Objections, AT VII.181. 17 See Zarka, “Le vocabulaire de l’apparaître,” 13–29; Schuhmann, “Phantasms and Idols,” 15–31. On the “phantasm” in the Short Tract, see Malcolm, Aspects of Hobbes, 130; Malcolm tends to reject the 14 200 journal of the history of philosophy 50:1 april 2012 precisely as the “image remaining” in front of one’s eyes after the end of the direct sensation, whereas in the so-called critique of Thomas White’s De mundo, and later in De corpore, Hobbes considers the phantasma manens as a constituent part of the imagination.18 This analogy is not insignificant,19 although not of itself sufficient proof of Hobbes’s paternity of the letter. However, Anonymous adds that it is not like a “phantasm” that Descartes intends the idea, and in particular the idea of God: sed negat Auctor Meditationum intelligere se talem Dei ideam. And it is this statement that should make us reflect, for where does Descartes deny (negat) this—that is, where does he deny that the idea, and in particular the idea of God, is an “image remaining in the fancy”? Not in the Meditations, where there is no trace of either fancy or phantasm (at least not under these names or with these meanings) and where, on the contrary, at the start of the Third Meditation, Descartes maintains that the term ‘idea’ properly fits only those thoughts that are “like images of things,” that is, that possess representative power.20 So in this case Anonymous cannot be alluding to the Meditations as such, but perhaps to some of the clarifications that Descartes had felt obliged to make during the subsequent debate: first in the Second Replies, to Mersenne, and then in the Third Replies, to Hobbes himself.21 These texts had not yet been published in May 1641 and were—as far as we know—known only to those directly involved (another fact that greatly reduces the shortlist of candidates for attribution of the letter). In his Third Objections, Hobbes had cited, with “cruel precision,”22 that very passage of the Third Meditation in which Descartes maintained that ideas are “like images of things,” and from this he had directly drawn the conclusion he was aiming at, that is, the impossibility thereby of knowing God: a conclusion that apparently hit home, given that the examples of idea-image in the Third Meditation included the idea of God (as well as that of man, chimera, angel, and heaven).23 This is why Descartes needed to take immediate corrective action in order to resolve the misunderstanding—which is what it was. And that is why, in the Third Replies, Descartes clarifies that he understands the term ‘idea’ very differently from Hobbes: he does not at all mean to indicate an image painted in the fancy, but every perception, and thus—as he had already explained to Mersenne—all attribution of the work to Hobbes, but his arguments are not entirely convincing. For Hobbes’s relations with the skeptical tradition, see Paganini, Skepsis, 171–227. 18 See Elements of Law, III.5, in EW IV.11; Hobbes, Critique du “De Mundo”, 350–51; De corpore, XXV.7, in OL I.322. 19 For Hobbes, the phantasm “remains” and persists because, in reality, it consists of the movement of the animal spirits, which cannot suddenly come to a halt even if it progressively becomes weaker; see Hobbes, Critique du “De Mundo”, 350–51 (idem motus sive phantasma manens); but also the preface to Mersenne’s Ballistics (OL V.310: the imagination as motus manens); and Leviathan, ch. 2. On the “persistence” of Hobbes’s phantasm, see also Pécharman, “Discours mental,” 553–73. 20 AT VII.37: [Q]uaedam ex his [cogitationibus] tanquam rerum imagines sunt, quibus solis propre convenit ideae nomen. 21 AT VII.139, 160, 165, 181. Having realized he must avoid all ambiguity on this point, Descartes returned to the question again in the Fifth Replies (cf. AT VII.366). 22 See Marion, “Hobbes et Descartes,” 61n7 (concerning AT VII.179); and Ariew and Grene, “Ideas,” 89. 23 AT VII.37: [U]t cum hominem, vel Chimæram, vel Cœlum, vel Angelum, vel Deum cogito. hobbes, descartes, and ideas 201 conscious content of the mind. Now, Anonymous appears to be referring precisely to this passage,24 thus already lifting the edge of his mask: Hic nomine ideæ vult [Hobbes] tantum intelligi imagines rerum materialium in phantasia corporea depictas; quo posito facile illi est probare, nullam … Dei propriam ideam esse posse…. Satis autem puto me explicuisse ideam Dei pro iis qui ad meum sensum volunt attendere; sed pro iis qui mea verba malunt aliter quam ego intelligere, nunquam possem satis. (Descartes, Third Replies, AT VII.181) Philosophorum vulgus per ideam significare solet conceptum simplicem, qualis est imago manens (ut loquuntur) in phantasia, quæ vocatur etiam phantasma. Sed negat Auctor Meditationum intelligere se talem Dei ideam. Neque, si sic eam intelligeret, ulla omnino Dei idea esse posset. (Anonymous, 19 May 1641) When it comes to the reasons why, in Anonymous’s view, an idea-image could never represent God, it is truly Hobbesian (although certainly not typical only of Hobbes): God is infinite and incomprehensible, thus He cannot be represented by our “imaginative faculty,”25 which is “capable only of sensible and finite things.” This was a position that Hobbes maintained in all his most important works: Neque dicetur [Deus] concipi sive comprehendi imaginatione, vel quacunque facultate animae nostrae; quicquid enim concipimus, finitum est.… Neque dici de Deo honorifice, quod idea ejus animo nostro insit; idea enim conceptus noster est; conceptus autem nisi finiti non est. (Hobbes, De cive, XV, 14; OL III.341) Whatsoever we imagine is finite. Therefore there is no idea or conception of anything we call infinite. And therefore the name of God is used, not to make us conceive Him (for He is incomprehensible, and His greatness and power are unconceivable), but that we may honour Him. (Hobbes, Leviathan, III; EW III.17) Est autem infiniti scientia finito quaesitori inaccessibilis; quicquid homines scimus a phantasmatis nostris didicimus, phantasma autem infiniti … nullum est. (Hobbes, De corpore, XXVI, 1; OL I.335) Si [Descartes] sic [ideam] intelligeret, ulla omnino Dei idea esse posset. Deus enim incomprehensibilis et infinitus non potest repræsentari per facultatem nostram imaginativam, quæ rerum sensibilium et finitarum tantum capax est. (Anonymous, 19 May 1641, AT III.376) 24 Note that, in his reply to the May 19 letter, Descartes was to stress yet again what he had said in the Second and Third Replies: Car je n’appelle pas simplement du nom d’idée les images qui sont dépeintes en la fantaisie; au contraire, je ne les appelle point de ce nom, en tant qu’elles sont dans la fantaisie corporelle; mais j’appelle généralement du nom d’idée tout ce qui est dans notre esprit, lorsque nous concevons une chose, de quelque manière que nous la concevions (AT III.392–93). 25 For the expression facultas imaginativa in Hobbes, see De Corpore, II.9 (OL I.18). He had already spoken of “imaginative power” in Elements of Law, I.7 (EW IV.2). 202 journal of the history of philosophy 50:1 april 2012 So it appears that already these preliminary analyses point to the possibility that the May 19 letter is, in reality, a brief counter-reply by Hobbes to Descartes’s Third Replies: perhaps an attempt to return, incognito, to the dialogue that had been brusquely interrupted. The subsequent passage gives much additional strength to this argument: it occupies the entire central portion of the letter, and deals with the idea of the sun. This example comes from Descartes (Third Meditation) but once again the first of the objectors to concentrate on it was Hobbes (followed, from a different perspective, by Gassendi).26 We have two ideas of the sun, Descartes had said in the Meditations: one, derived from our senses, represents it in reduced size; the other, an intellectual idea, represents it with the enormous dimensions astronomy has taught us.27 But he had said this almost en passant to introduce two themes: that of the dissimilarity between our sense perceptions and things as they are in themselves; and precisely that of the innate nature of mathematical notions and their independence from empirical contents. In his Third Objections, Hobbes pointed to this passage chiefly to criticize Descartes’s distinction between imaginative and intellectual ideas.28 For Hobbes, there can only be one idea at a time, and necessarily an imaginative idea. All reasoning (ratiocinatio) involves the manipulation of mental contents (ideas, i.e. sensory images, or names); such contents can be “added” or “subtracted” by the mind in order to conclude something (colligere), but this rational calculation can never give rise to the sort of intellectual, non-sensory ideas that Descartes proposed.29 The opposition between imaginari and (ratiocinando) colligere runs through all of Hobbes’s Third Objections, and is indeed the foundation of his entire critique of Descartes’s theory of knowledge. This same opposition, together with the tendency to deny that the intellectual process possesses any autonomy from the imaginative one, returns word for word in the May 19 letter, and once again it is applied to the case of our idea of the sun. The expressions are virtually identical, and there are also some telling points of correspondence with a passage from a later work of Hobbes’s (Problemata physica, 1662) on the “idea pedalis” (that is, having the diameter of one foot) of the sun.30 A similar passage is to be found in De corpore: 26 For Gassendi, see AT VII.283. Gassendi insists on this point above all to stress his empiricist criticism of innatism. For Descartes’s reply, see AT VII.363–64. 27 AT VII.39: [D]uas diversas solis ideas apud me invenio…. 28 Cf. Leijenhorst and Leijenhorst, Mechanisation, 94 ff. 29 AT VII.178 = OL V.257. 30 The reference to the idea pedalis of the sun is not original, indeed it has quite a history (from Aristotle’s De Anima to Cicero’s Academica). With his allusion, the author of the May 19 letter actually reveals the crypto-citation of Aristotle that Descartes had inserted in the Third Meditation (on Descartes’s strategy in this passage, and in general in Meditations, see Scribano, Angeli e beati, 134–60). hobbes, descartes, and ideas Solis idea unica uno tempore videtur esse, sive spectetur oculis, sive ratiocinatione intelligatur esse multoties major quam videtur. Nam hæc altera non est idea solis, sed collectio per argumenta ideam solis multoties fore majorem, si multo proprius spectaretur. Differentia magna est inter imaginari, hoc est, ideam aliquam habere, et mente concipere, hoc est, ratiocinando colligere rem aliquam esse, vel rem aliquam existere. (Hobbes, Third Objections; AT VII.178, 184 = OL V.257, 263) Quamquam enim sol, ut et omne corpus realiter existat et maneat, circulus tamen ille splendidus magnitudinis (ut videtur) pedalis, sol non est. (Hobbes, Problemata physica; OL IV.329) Qui solem intuetur existit illi idea quaedam splendida magnitudinis quasi … unius pedis; atque id ipsum appellat ille solem, etiam si solem revera multo majorem esse sciat … Si Sol ratiocinatione aliqua vera inveniatur major quam magnitudo apparens, magnitudo illa in sole non est. (Hobbes, De corpore, VI.8–9; OL I.66–67) 203 Ego … invenio … habere me per visionem quidem ideam solis consistentem circulo lucidissimo non magno.… Postquam autem ratiocinando collegerim solem multoties majorem esse quam idea illa quæ oculis apparuit, tunc vel fingo circulum ei æqualem, quæ semper est idea imaginativa, vel concipiens solem sine alia idea præter illam pedalem, dico tamen multo majorem eum esse quam videtur. (Anonymous, 19 May 1641; AT III.376–77) Descartes replied in two lines to Hobbes’s objections on the idea of the sun. In a highly irritated tone he argued that the intellectual idea of the sun was exactly what Hobbes was describing here, that is, the description of its properties based on astronomical research, translated into mathematical terms thanks to the inborn notions of geometry: Hobbes does not call it an idea, but I do (quod ego ideam voco).31 And Anonymous, probably replying to this very passage, fully twice concedes the point in his letter: I agree, let us call it that (si idea vocanda sit / si tamen idea vocanda est).32 Thus Anonymous’s argumentative strategy also emerges: a sort of concession for argument’s sake. All right, so we will maintain that abstract reasoning generates some “intellectual ideas,” as Descartes wants; and where does that lead us? Not far, it is implied. What is, or what would be, an “intellectual idea”? It would correspond not to a “simple term,” or a name, as does an imaginative idea (the disc of light that we call ‘sun’),33 but to a proposition, because with it we 31 AT VII.184. In his second reply to the May 19 letter, Descartes repeated it again, in connection with the idea of God and of the soul: Est-il croyable qu’il n’ait pu comprendre, comme il dit, ce que j’entends par l’idée de Dieu, par l’idée de l’âme, et par les idées des choses insensibles, puisque je n’entends rien autre chose, par elles, que ce qu’il a dû nécessairement comprendre lui-même, quand il vous a écrit qu’il ne l’entendait point? Car il ne dit pas qu’il n’ait rien conçu par le nom de Dieu, par celui de l’âme, et par celui des choses insensibles; il dit seulement qu’il ne sait pas ce qu’il faut entendre par leurs idées. Mais s’il a conçu quelque chose par ces noms, comme il n’en faut point douter, il a su en même temps ce qu’il fallait entendre par leurs idées, puisqu’il ne faut entendre autre chose que cela même qu’il a conçu (to Mersenne, July 1641; AT III.392). 32 AT III.376. 33 The question of the relationship between idea and “simple term” was to be raised again by Mersenne, as may be seen from Descartes’s letter of reply, 22 July 1641 (AT III.417–18). 204 journal of the history of philosophy 50:1 april 2012 positively affirm something, for example: “The sun has those dimensions that are attested by astronomical research.” Now, this observation of Anonymous’s, which refers to a distinction of Scholastic origin between the apprehension of simple concepts and their concatenation into a complex concept corresponding to a proposition,34 has a precise correspondence in a later text of Hobbes’s, illuminating it and at the same time being illuminated by it. Chapter 5 of De corpore, dedicated to different types of logical errors, also examines the error consisting of joining the name of a thing with the name of a proposition through the copula ‘is’ (§9). And, according to Hobbes, this is also the case of those who place ideas both in the fancy and in the intellect, as though the idea of man that we have via our senses were different from that we obtain when we comprehend with our intellect that man is an animal (whereas: unicam habemus ideam). Hobbes’s principal adversary is Descartes, as already his use of the term ‘idea’ shows; and indeed this point had already been touched on, as we have seen, in the Third Objections, again concerning the imaginative idea of the sun, which is the only one that there is any point in talking about (solis idea unica est).35 However, in De corpore Hobbes adds an observation, generally neglected by those who have examined this passage:36 the reason why we have fallen into the error of thinking that intellectual ideas exist is the fact that it had been thought that imaginative ideas corresponded to names, whereas intellectual ideas corresponded to propositions, which “is false” (that is, it is false that intellectual acts exist that correspond to propositions and differ from sensory images). It is clear that this is the same distinction proposed in the May 19 letter: it was Anonymous, indeed, who contested Descartes’s duplication of the idea between the imagination and the intellect, and who understood it—the better to criticize it—in terms of a distinction between names and propositions: Eundem errorem errant, qui ideas alias in intellectu, alias in phantasia ponunt; quasi alia esset idea sive imago hominis quae orta a sensu in memoria retinetur, alia quae in intellectu est, quando intelligimus hominem esse animal; id, quod imposuit, est quod nomini unam, propositioni aliam respondere rei ideam putaverint, quod est falsum. (Hobbes, De Corpore, V.9; OL I.54) Hæc, inquam, sunt quæ ego intelligo circa distinctionem inter ideam quam ponit ille in phantasia, et illam quam collocat in mente, sive intellectu, sive ratione. Invenio … habere me per visionem quidem ideam Solis consistentem circulo lucidissimo non magno; quæ idea simplici nomine exprimitur…. Postquam autem ratiocinando collegerim Solem multoties majorem esse quam idea illa quæ oculis apparuit …, dico tamen multo majorem esse quam videtur…. Sequitur ideam Dei exprimendam esse per propositionem, puta hanc: Deus existit, non per nomen unum tantum quod non est nisi propositionis pars. Similiter idea Poligoni 34 See Panaccio, Ockham, 31–35; Perez-Ilzarbe, “John Buridan,” 153–82; Pécharman, “Sémantique,” 203–36. 35 Similarly, in the May 19 letter, we read that the idea of a polygon that one has before and after having counted the sides eadem est, except that it is accompanied by knowledge that one did not have before. 36 See Marion, “Hobbes et Descartes,” 61; and Leijenhorst and Leijenhorst, Mechanisation, 94. hobbes, descartes, and ideas 205 quæ videndo acquiritur, eadem est in phantasia ante et post laterum numerationem; sed idea quæ latera numerando acquiritur (si tamen idea vocanda est) est conceptus complexus, et exprimitur propositione, puta hac: Figura hæc habet mille latera. (Anonymous, 19 May 1641; AT III.376–77) In a word, Anonymous implicitly relied on the very doctrine roughly sketched in the Third Objections and destined to be expounded in Hobbes’s greater works, starting from the critique of Thomas White’s De mundo: Intellection is not an autonomous mental act, independent of the imagination, that is, of the phantasm present in the mind; intellection does not generate any new ideas, but at most recalls to mind, through the corresponding name, the image of the thing thought.37 And reasoning is reduced to making a link, corresponding to the linguistic form of a proposition, between one name and another, in other words, to moving from one aspect to another of a perceived thing: in saying that “man is an animal” we think first of what we consider to be “man” and then, in succession, of what we consider to be “animal” as referred to the same thing.38 Hence the well-known dissolution of ratio into oratio, that is, the denial of rationality understood as an autonomous intellectual faculty and its reduction to a simple ability to join one name discursively to another.39 Thus, according to Anonymous, the idea of the sun that one conceives having been taught astronomical science is the same as before, or in any case it is always an imaginative idea; the difference is that now we may say, with a proposition, that the sun is much larger than it appears (dico tamen multo maiorem esse quam videtur). And already in the Third Objections, Hobbes had written that, diversis temporibus,40 one may have different ideas of the sun, one when one looks at it with the naked eye and another when one looks at it with a telescope, but that astronomical knowledge does not change the idea of the sun, making that idea larger or smaller: it simply lets us understand, through a mere rational calculation, that our sense idea is fallacious. After this long introduction, Anonymous—if we may still call him so—begins to move toward his conclusive argument, long prepared but now expressed in a few words (which amply justifies Descartes’s initial incomprehension, of which more below). He has established that the only sense in which we may speak of intellective ideas is that which enables us to consider them as corresponding to propositions, that is, to statements with which we attribute a predicate to a subject. Descartes’s idea of God, being of a strictly intellectual nature and excluding any 37 Hobbes, Critique du “De Mundo”, 126. In his reply to the May 19 letter, Descartes showed he had perfectly grasped this point: see the passage quoted above, n. 15. 38 Hobbes, De corpore, V.9: [A]d orationem hanc homo est animal unicam habemus ideam, etsi in ea idea prius id consideratur, propter quod vocatur homo, posterius vero id, propter quod vocatur animal (OL I.54). 39 See Elements of Law, V.14 (EW IV.25). 40 Third Objections, AT VII.184 = OL V.263. This temporal aspect is constantly present also in the May 19 letter (nisi lateribus prius numeratis—postquam autem ratiocinando collegerim—ante et post laterum numerationem). 206 journal of the history of philosophy 50:1 april 2012 image in the fancy, would thus be the equivalent—according to the letter-writer—of a proposition such as “God exists” in the same way that the intellectual idea of a chiliagon, i.e. a polygon with a thousand sides (the example comes from the Sixth Meditation), corresponds to the proposition that links the subject ‘this polygon’ to the predicate ‘to have a thousand sides.’ However, this passage also needs some clarification: why should the idea of God dealt with in the Meditations correspond precisely to the proposition “God exists”? Descartes’s astonished and scandalized reaction, on this point, is indicative: such a thing could never—he writes—have entered my mind.41 And we may suppose that he was not the only one to react in this way, which might also explain the lack of consideration given to the May 19 letter over subsequent centuries. The fact is that the idea of God, for Descartes, consists in the notion of an “infinitely perfect being” and only in this; to reduce it to the proposition “God exists” is for him pure nonsense, which goes against the “ordinary” way of reasoning.42 But Descartes did not know that he was dealing with a philosopher who was anything but ordinary: the position held by his anonymous adversary starts to make proper sense only if it is interpreted in the light of Hobbes’s position on the question of God. And this is a further confirmation—substantially decisive confirmation—of the letter’s attribution. For Hobbes, because there is not and could not be an imaginative idea of God, the only way to try to speak meaningfully of God is to reason, that is to link predicates to the name ‘God.’ Now, Hobbes notoriously held that the only positive attribute that we can assign to God is His existence; thus the only name that we can legitimately predicate of the subject ‘God’ in a proposition is the name that makes us conceive of Him as existing.43 For this reason, in the Third Objections, he had stated that with the term ‘God’ we intend firstly a substance—that is, we mean that “God exists”; and we intend it, he clarified, not through an idea but through a line of reasoning (as for the other attributes, far from enabling us to know God, they denote only our imperfection, and this holds above all and obviously for all those attributes that imply a reference to the infinite). In a text that was later, but not for that reason any less relevant, the Appendix to the Latin edition of Leviathan, Hobbes was to return to the question of the attributes of God, and he once more showed that the statement “God exists” (here compared to the formulae of the Council of Nicea: “God is the Father,” “God is omnipotent”) is in actuality a proposition on the nature of God, which can be resolved in the formula “God is an entity.” This formula constitutes, in Hobbes’s view, the entire content of rational theology. 44 41 Descartes to Mersenne, July 1641: Mais par quelle induction a-t-il pu tirer de mes écrits, que l’idée de Dieu se doit exprimer par cette proposition Dieu existe …? Il faut qu’il ait vu bien clair, pour y voir ce que je n’ai jamais eu intention d’y mettre, et ce qui ne m’était jamais venu en pensée, devant que j’eusse vu sa lettre (AT III.395–96). 42 Descartes to Mersenne, July 1641: J’ai tiré la preuve de l’existence de Dieu de l’idée que je trouve en moi d’un être souverainement parfait, qui est la notion ordinaire que l’on en a (AT III.395–96). 43 See Elements of Law, XI.2; and Critique du “De Mundo”, 395–96. 44 Cf. OL III.512: [I]llud Deus est, significat idem quod Deus existit, id est, resoluto verbo substantivo, Deus est en … id est, reale aliquid, non merum phantasma. Martinich is not wrong to point out how unusual it is to consider the proposition ‘God is’ (or “God exists”) as a proposition concerning the nature of God, and not as the simple assertion of His existence (see Martinich, Two Gods, 196). hobbes, descartes, and ideas 207 Now it is clear that, on this point too, the May 19 letter precisely echoes Hobbes’s position, through which he tries to reinterpret Descartes’s position: Dei nomine intelligo substantiam, hoc est intelligo Deum existere (non per ideam sed per ratiocinationem). (Hobbes, Third Objections, AT VII.186–87 = OL V.265) Nullam propositionem veram esse posse circa naturam Dei praeter hanc unam: Deus est. (Hobbes, Critique du “De Mundo,” 395–96) Idem est habere ideam Dei, et ratiocinando inferre Deum existere. Per ideam Dei intelligit [Descartes] cognitionem (per rationem) hujus propositionis, Deus existit. (Anonymous, 19 May 1641, AT III.377) From this standpoint, entirely and uniquely Hobbesian, the passage from the presumed intellectual idea of God of the Third Meditation to the mere ratiocinatio with which it is established that “God exists”—taken almost for granted by Anonymous—becomes comprehensible; indeed it becomes the only way to translate meaningfully Descartes’s idea Dei. And this despite the fact that Anonymous, once again not venturing too openly, tries to make us believe that the example is chosen at random: “sequitur ideam Dei exprimendam esse per propositionem, puta hanc: ‘Deus existit.’” But that this is simply one more tactical expedient is confirmed by the rest of the letter: the criticism of the proof of the existence of God in the final part (on which more shortly) holds if, and only if, we admit that Descartes’s idea of God corresponds univocally and necessarily to the proposition “God exists” (and this shows us just how fragile that puta hanc actually is).45 The only real difference from Hobbes’s official texts is that here, as we have already said, he verbally concedes to Descartes the possibility of speaking of an “idea of God” (only to spoil this by repeating that to have an idea of God only means to be able to infer, ratiocinando, that God exists). We now come, however, to the decisive short-circuit: if to have the idea of God means—according to the Hobbesian approach of Anonymous—to discursively conceive as existing an entity called God, then it is clear that the presumed “demonstration” of the existence of God starting from that idea, that is from that line of reasoning, instantly becomes a mere begging of the question (petitio principi). And thus it is defined, indeed, in the May 19 letter.46 With Descartes’s idea Dei, the supporting pillar of the entire Meditations, either we must presuppose what we are to demonstrate, and thus we demonstrate nothing, or we demonstrate one thing through that same thing (idem per idem), which hardly improves matters, nor does it make the argument any less sophistic. And it is this that places Hobbes’s signature on the May 19 letter: existence is the only attribute of God that is predicable in a sensible manner, but for that very reason, to prove the existence of God starting from His “idea” is finally a bare tautology, that amounts to nothing more than saying “if God exists then God exists.” 45 See again the passage of the critique of De mundo quoted above: ‘God exists’ is the only true proposition that can be constructed with the name ‘God,’ and the only one that tells us something about the divine nature. 46 AT III.377: [E]rit summa argumentationis qua probat Deum existere petitio principii. 208 journal of the history of philosophy 50:1 april 2012 Having launched his final objection against the idea of God, the letter-writer concludes by devoting a line to the question of the incorporeal nature of the soul—another of Hobbes’s pet subjects. For the author of the letter, the same logical flaw (vitium) present in Descartes’s proof of the existence of God is also to be found in his claimed demonstration that the soul is a thinking substance distinct from the body. In his Third Objections, Hobbes had already explained what constituted this flaw: Descartes “assumes, but does not prove” that the mind cannot be the property of a corporeal substance. In the Meditations, the existence of an intellectual idea of the soul is postulated, which, in reality, as in the case of the idea of God, is merely a line of reasoning; and the proposition that derives from it is limited to linking a subject with some predicate, but says nothing against the possibility of the subject itself being corporeal.47 And the final diagnosis of the May 19 letter corresponds to that issued by Hobbes a few months earlier: Potest ergo esse ut res cogitans sit subjectum mentis, rationis, vel intellectus, ideoque corporeum aliquid: cujus contrarium sumitur, non probatur. (Hobbes, Third Objections, AT VII.173 = OL V.253) [Descartes] enim sumit, sine probatione, quod datur idea Dei … Idem vitium est in argumentatione qua probare vellet, Animam existere incorpoream. (Anonymous, 19 May 1641, AT VII.377) From all of this, the extreme difficulty of denying Hobbes’s paternity of the May 19 letter emerges clearly: the terminology used, the positions argued, the biographical and historical contingencies, the numerous points of correspondence with Hobbes’s previous, contemporary or future works, but above all the fact that the letter can only really be understood against the background of Hobbes’s metaphysical ideas. The only obstacle to such an attribution relates to Hobbes’s decision—which we may assume he made consciously—not to venture too far into the open, as somewhat imprudently he had done with the first missive sent to Descartes in November 1640 (in which he maintained apertis verbis that God is material)48 and to a lesser extent in the Third Objections. Instead of propounding his own doctrines, Hobbes tries in this letter to follow Descartes’s arguments without taking an explicit position on the nature of human ideas. This change of critical attitude (which is probably another cause of Descartes’s inability to recognize Hobbes’s hand) could be the outcome of a new and more attentive reading of the Meditations. When writing his Third Objections, Hobbes had not considered the passage of the Sixth Meditation concerning the “chiliagon”: this was, in fact, the only passage of the whole Meditations where the question of the distinction between imaginatio and pura intellectio was discussed thematically.49 Descartes himself, in his reply to the Third Objections, had alluded to this passage,50 probably 47 See AT VII.183 = OL V.263: [N]ulla omnino animae est idea, sed ratione colligimus esse aliquid internum corpori humano quod ei motum impertit animalem, quo sentit et movetur; atque hoc, quidquis est, sine idea vocamus anima. 48 The letter has been lost, but its content may be reconstructed thanks to Descartes’s reply; see Schuhmann, Hobbes, 60–63. 49 See AT VII.72. Hobbes’s only objections to the Sixth Meditation concerned the question of God’s veracity and the distinction between dream and reality. 50 See AT VII.178: [S]ed et alibi explicui quo pacto unam et eandem rem, puta pentagonum, aliter intelligamus, et aliter imaginemur. hobbes, descartes, and ideas 209 arousing Hobbes’s curiosity and stimulating him to return to the manuscript of the Meditations. This, we may suppose, was also the contingent occasion for the May 19 letter, which—as we have seen—quotes this very passage and correctly links it to the question of the idea of the sun that Hobbes had already mentioned in the Third Objections. It is as though, for Hobbes, the Sixth Meditation shed new light on the Third: he now interprets the “intellectual idea” as the Cartesian counterpart of the Scholastic conceptus complexus,51 i.e. a mental state corresponding to a proposition through which we conceive of a thing and its properties (Descartes himself seemed to have assumed, in the Sixth Meditation, that thinking of a chiliagon is conceiving that “it is a figure composed of a thousand sides”).52 Contrary to the Third Objections, however, Hobbes does not deny here the possibility of a Cartesian “intellectual idea.” He limits himself to using this concept as a weapon in his battle against Descartes’s proof of the existence of God: if having the intellectual idea of a chiliagon means only to define it through a proposition such as “it is a figure composed of a thousand sides,” then having the intellectual idea of God can only mean to define Him through a proposition such as “God exists”—by which the existence of God is affirmed, but not proven in any sense of this word. If anything, the question remains what proof, or what arguments for the existence of God, Hobbes has in mind in the May 19 letter. In his first reply, Descartes appears to believe that his objector’s criticism concerns the argument that will later to be called “ontological,” that he returns to and reinterprets in the Fifth Meditation;53 and in this initial opinion he was to be followed by other more recent readers. But Descartes has a much more ambiguous attitude in his second reply: he starts by saying that the author of the May 19 letter is attacking la principale raison dont je me sers pour prouver [l’]existence [de Dieu] (this being the way in which he qualifies, in at least three texts of that period, the a posteriori proof of the Third Meditation); but then, describing the dynamics of the proof he has in mind, he returns again to using the formulae he had employed initially (the definition of God as antecedent for the demonstration that God exists).54 In the attempt to verify how things stand at least from Hobbes’s side, however, we should take into account the fact that, already in the Third Objections, the sole proof of the divine existence that he considered was that of the Third Meditation (in reading the Fifth Meditation, Hobbes had only lingered on the question of the essence of material things). Now, in the Third Objections, Hobbes had insisted on the very fact that Descartes proceeds from the thesis quod habemus ideam Dei to the conclusion 51 See the passage, already quoted, of the May 19 letter: [I]dea quæ latera numerando acquiritur (si tamen idea vocanda est) est conceptus complexus, et exprimitur propositione, puta hac: Figura hæc habet mille latera (AT VII.377). Hobbes was undoubtedly aware of the Scholastic discussions mentioned above (on his studies of Scholastic logic as a young man, see Schuhmann, Hobbes, 23). 52 AT VII.72: Si vero de chiliogono velim cogitare, equidem aeque bene intelligo illud esse figuram constantem mille lateribus. In his second reply to the May 19 letter, Descartes was to deny that, for him, an intellectual idea corresponds always to a proposition (AT III.395). 53 Indeed, in this first reply, Descartes equates the deduction of the existence of God starting from the idea of God to a mathematical theorem, as in the proof in the Fifth Meditation (AT III.383). 54 AT III.395. For the “principal” proof of the existence of God, see AT VII.14, 101, 238. Henri Gouhier hypothesizes, but not persuasively, that here too Descartes was referring to the ontological proof, thus contradicting the other declarations on the “principal” way to demonstrate the existence of God (Gouhier, Pensée métaphysique, 166). See also Wilson, Ideas and Mechanism, 105n2. 210 journal of the history of philosophy 50:1 april 2012 quod Deus existat, seeing in this inference the core of the a posteriori proof of the Third Meditation. And it is on this same inference that the May 19 letter insists, prolonging the debate opened with the Third Objections also on this point. The question Descartes is accused of begging in the May 19 letter, indeed, does not in any way concern the step from defining an infinitely perfect being to asserting its real existence, as in the “ontological” argument; just as in the Third Objections, the question is the step from the fact that one has an idea of God (quod datur idea Dei) to the positive assertion: Deus existit. The difference from the previous text, once again, is that there he denied the premise (that is, he denied that an idea of God existed) whereas here it is verbally conceded, but reducing the idea of God to the simple proposition “God exists,” thus nullifying Descartes’s demonstration: Jam quoniam ex positione hac, quod habemus ideam Dei in anima nostra, procedit D. [Cartesius] ad probationem hujus theorematis, quod Deus … existat, oportuit illam ideam Dei melius explicare. Si non detur Dei idea (non autem probatur dari) quemadmodum non dari videtur, tota haec collabitur disquisitio. (Hobbes, Third Objections, AT VII.183 = OL V.263) Vel enim sumit, sine probatione, quod datur idea Dei, et per ideam Dei intelligit cognitionem (per rationem) hujus propositionis, Deus existit; et sic sumit quod debebat probare. Vel non sumit, sed probat, dari ideam Dei, per hoc quod ratiocinando possumus inferre Deum existere; et sic probat idem per idem: idem enim est habere ideam Dei, et ratiocinando inferre Deum existere. (Anonymous, 19 May 1641, AT VII.377) Thus what we have in these texts of Hobbes’s is not a criticism of the ontological proof, but the simple analysis of the so-called “idea of God.”55 Given the resolution of that presumed idea into a mere ratiocinatio by which it is affirmed that God exists, the entire complex scaffolding of Descartes’s proof (formal reality, objective reality, notion of infinitely perfect being) becomes completely superfluous. Of course, from Hobbes’s standpoint, one may always say that God exists, because the only predicate that may be attributed to God is precisely that of existence. An “ontological” argument—if one still wants to call it thus—that has been pruned right down but, above all, one that has been freed from the logic of infinite perfection. And it was here that, in his second reply to the May 19 letter, Descartes saw the germ of impiety: if we renounce the idea of God as infinitely perfect, we reduce God to a mere being, without any further qualification, precluding all possibility of knowing Him and adoring Him (and thus—implicitly—precluding all possibility of basing human knowledge on His veracity).56 This is the real point, the point 55 Yves-Charles Zarka sees in Hobbes a criticism of the ontological argument based, as that of Gassendi in the Fifth Objections, on the denial that existence is a predicate (Zarka, Décision métaphysique, 147 ff.). But for Hobbes existence is certainly a predicate (for him Deus est corresponds to Deus est ens, because the verb ‘to be,’ in this case, contains in itself tum copulam tum praedicatum; OL III.512) and it is a predicate included in the name ‘God’; this does not, however, demonstrate anything about the real existence of God, and in this his implicit criticism of the ontological argument is closer to that of Aquinas than to that of Gassendi and later Kant. 56 Et l’on aurait beau dire, par exemple, qu’on croit que Dieu est, et que quelque attribut ou perfection lui appartient, ce ne serait rien dire, puisque cela ne porterait aucune signification à notre esprit; ce qui serait la chose la plus impie et la plus impertinente du monde (AT III.394). hobbes, descartes, and ideas 211 noted by Descartes, and it reveals what is behind the May 19 letter—especially when we remember that, for Hobbes, existence signifies corporality. In his view, just as to say that “man exists” means arguing that, among the bodies of the universe that constitute the field of being, there is one that we call ‘man,’57 similarly, to say that “God exists” is to say that, if something real corresponds to the name ‘God,’ this something is a part of the corporeal universe or that it is identified with it. Hobbes himself later raised this alternative, in a reply to Bramhall,58 but without clearly choosing between the two horns of the dilemma, both rather uncomfortable and certainly irreconcilable with any orthodox theology of the time. From the criticism of ideas to the criticism of theology, in a word, there is only a small step. And Descartes, though without understanding much of Hobbes’s convoluted arguments, could not and did not let this point escape him. bibliography and abbreviations Ariew, Roger, and Marjorie Grene. “Ideas, in and before Descartes.” Journal of the History of Ideas 56 (1995): 85–106. 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