SIMONE GUIDI Descartes and the ‘Thinking Matter Issue’ ABSTRACT: In this paper, I aim to address a specific issue underpinning Cartesian metaphysics since its first public appearance in the Discourse right up until the Meditations, but which definitely came to the surface in the Second and Fifth Replies. It involves the possibility that to be thinking and to be extended do not actually contrast as two entirely different properties; hence, these two essences cannot serve as the basis for a disjunctive, real distinction between two corresponding substances, the mind and the body. I dub this problem the ‘thinking matter issue.’ I suggest that Descartes’s concerns about the ‘thinking matter issue’ characterizes and structures the entirety of Meditation Two and its connection with Meditation Six, especially in the attempt to covertly implement what I refer to as Descartes’s ‘prejudice strategy.’ The core of the ‘prejudice strategy’ lies in the idea that the ‘thinking matter issue’ is just a false problem, one raised by the inadequate notions of the mind and the body that we apply to this problem. SOMMARIO: In questo articolo mi propongo di affrontare una decisiva questione alla base della metafisica cartesiana, presente fin dalla sua prima apparizione pubblica nel Discours e poi nelle Meditationes, eppure definitivamente esplicitata solo nelle Responsiones Secundae e Quintae. Si tratta dell’eventualità che essere pensante e essere esteso non si contrappongano come due proprietà interamente diverse; di conseguenza, le loro essenze non possono fornire una base incrollabile per una distinzione disgiuntiva e reale tra due corrispondenti sostanze, la mente e il corpo. Con riferimento alle successive osservazioni di Locke su questo punto, chiamo questo problema ‘thinking matter issue’. Tesi centrale dell’articolo è che la preoccupazione di Descartes per la ‘thinking matter issue’ caratterizzi e strutturi l’intera Meditatio Secunda e la sua connessione con la Meditatio Sexta, soprattutto nel tentativo di attuare implicitamente quella che definisco la ‘strategia del pregiudizio’. Il nucleo della ‘strategia del pregiudizio’ risiede nell’idea che la ‘thinking matter issue’ sia in ultima analisi solo un falso problema, suscitato dalle nozioni inadeguate di mente e corpo a cui ricorriamo. KEYWORDS: Descartes; Mind-Body Distinction; Thinking Matter; Prejudice; Childhood INTRODUCTION In this paper I aim to address a specific issue underpinning Cartesian metaphysics since its first public appearance in the Discourse until the Meditations, but that definitely comes to the surface only in the Second and Fifth Replies. It is the possibility that to be thinking and to be extended do not actually contrast as two entirely different properties; hence, these two essences cannot serve as the basis for a disjunctive, real distinction between two corresponding substances, the mind and the body. I dub this problem the ‘thinking matter issue’. It should go without saying that such a hypothesis might jeopardize Descartes’s whole philosophy, and particularly his efforts to claim that the mind and the body are so distinct that we can indisputably demonstrate their real distinction. Yet, for reasons ARTICLES-LE LEXIQUE DE LA MÉTAPHYSIQUE CARTÉSIENNE ISSN Lexicon Philosophicum, n. 10 (2022) 2283-7833 • HTTP://LEXICON.CNR.IT/ 182 simone guidi that I will endeavor to make clear in this article, Descartes is not only aware of this possibility, as of 1638 at least, but he even makes this problem a pivot of the whole, mature argumentative path through which he tries to prove his mind-body dualism. In particular, his treatment of this problem covertly runs through the entire chain of arguments connecting Meditation Two and Six, and so is the crucial structure that binds the cogito and the demonstration of the real distinction between the mind and the body. Despite this strategic importance, Cartesian scholarship has traditionally undervalued the role played by the ‘thinking matter issue,’ which is rarely found listed in critical literature among other more famous problems traditionally constituting Descartes’s philosophy.1 My aim here, therefore, is to provide a clear understanding of how this issue takes place in Descartes’s thought and to chart the strategies Descartes adopts to face it. However, this implies dwelling on two aspects in particular: on the one hand, Descartes’s own work to devise sound argumentative paths to demonstrating his dualism in spite of the ‘thinking matter issue’; on the other hand, his adversaries’s critiques, who constantly try to dismantle these paths and compel him to reveal his premises. As far as this second aspect is concerned, my idea is that Descartes’s real position about the ‘thinking matter issue’ is overtly revealed in his Replies to Mersenne and Gassendi. Only the dialogue with his opponents prompts Descartes to bring out his premises and to elucidate the strategy that he adopted in the Meditations more clearly. 1. THINKING THINGS The sequence of arguments holds particular importance in Descartes’ thought, as a philosophy structured more geometrico. Yet, it is quite evident that something has changed when it comes to comparing the structure of Descartes’s demonstration of his mind-body dualism in the Discourse with that in the Meditations. As I shall argue, the specific arrangement that Descartes adopts in 1641 takes the ‘thinking matter issue’ into account as a fundamental problem, and this distinguishes the ‘complex argument’ presented in the Meditations for the mind’s spirituality from the still ‘simple argument’ that he had set out in the Discourse.2 Let us delve into this point starting with the Discourse. In his 1637 metaphysics, Descartes had clearly derived the mind’s spirituality from the indisputable existence of the mind (proven by the cogito argument and as the outcome of a restricted version of the doubt, limited to the existence of material things only).3 Indeed, in the Discourse, 1. As far as I am aware, this problem was quite expressly addressed by Hooker 1978, Donagan 1978, Buccolini 2010, Landucci 2021: 53-83. The same issue, albeit from a slightly different perspective, is also addressed by Frankfurt 1970: 154-174 (particularly 167-174). See also Guidi 2018: 311-360. As for Gilson and Gueroult see below, note 28. 2. Concerning the difference between Descartes’s metaphysics in the Discourse and the Meditations, see especially Alquié 1950: 147-158; Kenny 1968: 40-95; Rodis-Lewis 1971: 208-213; Rodis-Lewis 1987; Marion 1991: 66-73. See also Guidi 2018: 320-333. 3. See AT VI, 32-33; CSM, 127: “considering that the very thoughts we have while awake may also occur while we sleep without any of them being at the that time true, I resolved to pretend descartes and the ‘thinking matter issue’ 183 the cogito argument was one thing with an ‘argument from doubt’ the function of which was to persuade the reader to believe that the essence of the mind cannot be material. We will find it reiterated several times in Descartes’ works.4 I refer to this as the ‘die-hard mind argumentD’,5 and I present it according to a slightly reworked version of the formulation provided by Norman Malcom: D1: I can doubt that I [who am thinking] have a body. D2: I cannot doubt that I [who am thinking] exist [i.e., the cogito] E: Ergo, I [who am thinking] am not a body.6 [And hence I, who am thinking, am only thinking] According to what Descartes contends in the Discourse, the non-bodily nature of the ego (E) spontaneously comes to the surface within and as a consequence of the cogito itself (D2), via the exclusion of the bodies, which may certainly be doubted (D1).7 I can that all the things that had ever entered my mind were no more true than the illusions of my dreams. But immediately I noticed that while I was trying thus to think everything false, it was necessary that I, who was thinking this, was something. And observing that this truth ‘I am thinking, therefore I exist’ was so firm and sure that all the most extravagant suppositions of the sceptics were incapable of shaking it, I decided that I could accept it without scruple as the first principle of the philosophy I was seeking. | Next I examined attentively what I was. I saw that while I could pretend that I had no body and that there was no world and no place for me to be in, I could not for all that pretend that I did not exist. I saw on the contrary that from the mere fact that I thought of doubting the truth of other things, it followed quite evidently and certainly that I existed; whereas if I had merely ceased thinking, even if everything else I had ever imagined had been true, I should have had no reason to believe that I existed. From this I knew I was a substance whose whole essence or nature is simply to think, and which does not require any place, or depend on any material thing, in order to exist. Accordingly this ‘I’ – that is, the soul by which I am what I am – is entirely distinct from the body, and indeed is easier to know than the body, and would not fail to be whatever it is, even if the body did not exist”. Famously, in the Meditations Descartes will push his methodic doubt up to the ‘hyperbolic’ level of Meditation One. Even if this constitutes an important element in the reshaping of the cogito and the mind-body distinction, I do not think it has a particular role in the way Descartes derives the spirituality of the mind from the cogito argument in the Meditations (see below). 4. In addition to the Discourse and the Meditations, see The Search for Truth by Natural Light (AT X, 518; Descartes 1955: I, 319) and the Principles, I, 7-8 (AT VIII-1, 6-7). 5. I use the letter ‘D’ in subscript to differentiate this version of the ‘die-hard mind argument’ set out in the Discourse from that put forth by Descartes in the Meditations, later indicated as ‘die-hard mind argument M’. 6. Malcom 1965: 329. 7. Indeed, like to Malcom (1965: 328-329), it seems to me that the clearest formulation of Descartes’s simple argument is that provided in The Search for Truth by Natural Light (AT X, 518; Descartes 1955: I, 319): “I do not even know that I have a body, since you have shown me that I might doubt of it. In addition to this I may add that I cannot even absolutely deny that I have a body. Yet, while entirely setting aside all these suppositions, this will not prevent my being certain that I exist. On the contrary, they confirm me yet more in the certainty that I exist and that I am not a body; otherwise, doubting of my body I should at the same time doubt of myself, and this I cannot do; for I am absolutely convinced that I exist, and I am so much convinced of it, that I can in no wise doubt of it” (my emphasis). Here, Descartes has not yet posed the ‘thinking matter issue.’ Of course, doubting the existence of bodies is not doubting the nature 184 simone guidi doubt the existence of the bodies, but not the existence of the ego; so, not only must I exist as a thinking thing, but I also cannot be a body as such; therefore, I must be an immaterial thinking thing. Famously, this bundle of intuitions8 constitutes a paradigmatic case of the clear and distinct, evident knowledge we should take as the model for all our knowledge for Descartes, and which is guaranteed by God as the non-deceiver maker of our minds. Hence, it has played a fundamental role in Descartes’s metaphysics since the Discourse. Unfortunately, as Malcom himself noted, the (E) inference of the ‘die-hard mind argumentD’ is not compelling from several points of view. Chiefly, from the fact that I or anyone can have doubts about a thing does not follow that I am not or one is not that thing.9 This makes the cogito argument a sound argument to demonstrate that I exist and that I think, but not the sufficient premise for a demonstration that I am only a thinking thing. of bodies or of my nature. I may infer from the cogito argument that I cannot doubt my own existence; but I can simultaneously accept that I am one of the bodies whose existence I doubted. 8. Descartes considers the cogito and what I call the ‘die-hard mind argument’ as prime examples of the possibility for the human mind to achieve intuitive knowledge and to deduce new intuitions from it. According to Wilson 1976: 9 (with whom I agree), they are intuitions of what Descartes in the Rules defined as “simple natures.” On Descartes’s notion of ‘intuition’ see Beck 1952: 47-99, Schouls 1970 and 1972, Markie 1979, Machamer & Adams 2014, Guidi 2021. On the intuitive-performative nature of the cogito, see the famous Hintikka 1962 and Kenny’s comments on it (1968: 40-62). 9. Consider, for instance, these two counter-arguments put forth by him: “[1)] It might be true of a man that he could doubt that he is a Grand Master of the Elks but could not doubt that he exists: it would not follow that he is not a Grand Master of the Elks. [2)] It might be true that I could not doubt that Bertrand Russell exists but I could doubt that the author of the pamphlet ‘Why I Am Not a Christian’ exists: it would not follow that Bertrand Russell is not the author of that pamphlet” (Malcom 1965: 330). Hooker 1978: 173-174, proposes this version of Descartes’s argument, which might escape similar critiques. Hooker calls it the ‘argument from conceivability’ and considers it to be valid (numbering starts from 12 and skips 13): “(12) I can conceive of myself existing and no bodies existing. (14) (P) (if p is conceivable, p is possible). (15) It is possible that I exist and no bodies exist. (16) (x) (if x is a body, x is essentially a body) [This principle is from Plantinga 1970: 483-487: 485]. (17) If I am a body, I am essentially a body. (18) If I am essentially a body, it is not possible that I exist and no bodies exist. (19) I am not essentially a body. (20) I am not a body.” It seems to me that this is a good formalization of Descartes’s genuine argument, but I think that it is far from valid. Indeed, the following premise is covertly introduced in Hooker’s argument as a principle (14’) (P’): ‘if p is conceivable, p is possible and its contrary is not conceivable’. Otherwise we may easily have (15’): ‘it is possible that I exist and the body exist, and it is also possible that I exist and the body exist’. In this case, we would have also (16’): ‘It is possible that I am a body and I exist and the body exist’. In (18) this argument means indeed that ‘If I am essentially a body, it is not possible to conceive that I exist and no bodies exist’, or ‘it is not possible that simultaneously I exist and no bodies exist’, and not that ‘it is not logically possible that I exist and no bodies exist’, unless we have (14’). The latter is, in effect, Descartes’ principle of ‘clear and distinct’: everything that I perceive clearly and distinctly is necessarily and logically true. In this paper, I will endeavor to show that the ‘clear and distinct’ principle is a hidden premise of his dualism, through what I refer to as the ‘prejudice strategy’ (see below). descartes and the ‘thinking matter issue’ 185 As I have endeavored to argue elsewhere,10 Descartes probably encountered these critiques much earlier than in our age. Indeed, in the Preface of the Meditations11 he himself acknowledges the limits of his 1637 philosophy, and of the ‘die-hard mind argumentD’ in particular, based on certain critiques that he received from his contemporaries Marin Mersenne12 and René Pollot in the aftermath of the Discourse. Both of Descartes’ correspondents pointed out that one cannot infer the spirituality of the mind (E) from our psychological experience of its immateriality, and from the fact that we can put the material world in brackets by the methodic doubt (D1) which we are unable to apply to ourselves (D2).13 The main difference between today’s critiques and the remarks Descartes received from his correspondents resides in the fact that the latter did not appear in a purely logical form. They are advanced in the form of a sneaky hypothesis that Descartes likely underestimated when writing the Discourse. In effect, it might still be the case that our thought stems from some material activity of bodies, ultimately relying on the organs of a material substance that is capable of thought. In this case, I might doubt that bodies exist (D1), but I am not allowed to judge that I, who certainly exists, am not a body (E). This is, in greater detail, what I hinted at previously as the ‘thinking matter’ theory or issue.14 It is expressed quite ef10. See Guidi 2018: 311-360. 11. In the Preface of the Meditations, Descartes evokes two critiques he received after the Discours. The first one is as follows: “From the fact that the human mind, when directed towards itself, does not perceive itself to be anything other than a thinking thing, it does not follow that its nature or essence consists only in its being a thinking thing, where the word ‘only’ excludes everything else that could be said to belong to the nature of the soul.” (AT VII, 8; CSM, 7). I addressed the relevance of these criticisms for the evolution of Descartes’s position in Guidi 2018: 311-333. 12. Mersenne’s objection can be found in a letter that is currently lost. However, we can infer his critique from Descartes’ reply to his letter to him, written around April 20, 1637 in Leiden (AT I, 349-350): “As far as your second objection goes, namely that I have not explained at length how I know that the soul is a substance distinct from the body, and whose nature is solely to think…” (my translation). See Buccolini 2010, especially on Mersenne’s own position and his arguments against the hypothesis at stake here. On the Mersenne-Descartes relationship, in more general terms and specifically concerning metaphysical issues, see Buccolini 1998, 2000, and 2019. 13. See AT VI, 31-32; CSM, 127. 14. I take this expression from Lockean scholarship (see for instance Yolton 1984 and 1991; Yolton & Yolton 1984; Hamou 2004; Brandt Bolton 2015; Jolley 2015: 67-83), where it is used to refer to the problem posed by John Locke in his Essay (1690). Locke posed it as follows: “after all, I think I may, without injury to human perfection, be confident, that our knowledge would never reach to all we might desire to know concerning those ideas we have; nor be able to surmount all the difficulties, and resolve all the questions that might arise concerning any of them. We have the ideas of a square, a circle, and equality; and yet, perhaps, shall never be able to find a circle equal to a square, and certainly know that it is so. We have the ideas of matter and thinking, but possibly shall never be able to know whether any mere material being thinks or no; it being impossible for us, by the contemplation of our own ideas, without revelation, to discover whether Omnipotency has not given to some systems of matter, 186 simone guidi fectively by two interlaced remarks on the Discourse advanced by Pollot in 1638: 3. To say that one cannot breathe without a body, but can think without it, is what should be demonstrated through a clear proof. Although it is possible to imagine not having a body (though this is quite difficult) and to live without breathing, it does not follow that it is actually so or that one can live without breathing. 4. It should be proven that the soul is able to think without the body. Aristotle does indeed presuppose this in one of his axioms, but he does not prove it. He believes that the soul can act without organs, from which he concludes that it can exist without them; however, he does not prove the former, which is contradicted by experience: for we see that those with an ailing imagination do not think well; and if they had neither imagination nor memory, they would not think at all.15 As stressed by Claudio Buccolini in particular,16 the ‘thinking matter’ theory circulated widely during Descartes’ time as part of a materialistic view of the soul. Mersenne himself had grappled with it on many occasions before the Discourse, not by accident, within his controversy against those who, like Pomponazzi, claimed that the rational soul is mortal.17 In effect, as emphasized here by Pollot (and then by Pierre Gassendi in particular in his Fifth Objections),18 this hypothesis corresponded to that of a corporeal phantasia praestantissima, a very powerful imagination whose activity was supposed to be located in the brain. This corporeal imagination should be able to bring about the thinking activity that the scholastics had ascribed to the human intellect. In the final analysis, hence, the ‘thinking matter theory’ coincided with the idea of a ‘organ of thought,’ and particularly with the hypothesis that imagination, through the brain, was able to produce the thinking activity Descartes considers as an essential and exclusive property of the ‘thinking thing’; that, therefore, would be a material thing. This simple theory was able to undermine Descartes’s 1637 approach. In order to show how harmful it would be for the purposes of Descartes’s metaphysics, it is fitly disposed, a power to perceive and think, or else joined and fixed to matter, so disposed, a thinking immaterial substance: it being, in respect of our notions, not much more remote from our comprehension to conceive that God can, if he pleases, superadd to matter a faculty of thinking, than that he should superadd to it another substance with a faculty of thinking; since we know not wherein thinking consists, nor to what sort of substances the Almighty has been pleased to give that power, which cannot be in any created being, but merely by the good pleasure and bounty of the Creator” (Locke 1975: IV, ch. III, §6). Note that there is no difference between the hypothesis of ‘thinking matter’ and the hypothesis of ‘extended thought’ for the peculiar dualistic approach employed by Descartes since the Discourse. Both are hypothesis of a structural intermingling between two things that are essentially and disjunctively different from each other. 15. See Pollot to Reneri for Descartes, The Hague, February 1638 (my translation). 16. See Buccolini 2010. 17. See Buccolini 2010: 10-12, reports especially the cases of Gabriel Potevin, the author of Clangor buccinae (1624), immediately flagged between the erroneous theses by Jean-Baptiste Morin in his Réfutation de thèses erronées and hence well-known by Mersenne himself; and the atomistic theses of Nicholas Hill, David van Goorle and Sebastien Basson (confuted by Mersenne in L’Impieté des déistes [1624]). 18. See in particular Buccolini 2010: 14. descartes and the ‘thinking matter issue’ 187 sufficient to consider the following consequence. By affirming that thought could entirely be boiled down to the body, this hypothesis alone shakes the very basis of Descartes’ idea that the distinction between the mind and the body can be demonstrated more geometrico starting from the cogito. Indeed, once this hypothesis is raised, then no demonstration based on the psychological certainty about a ‘thinking thing’ can help us to rule it out. The only way that we have (and Descartes had) to escape this snare is to reverse the game and to eradicate this theory by involving it in the general theory that our mistakes are caused by preconceived ideas19 and showing that it is simply implausible in its bases. In the following sections, I will argue that this is Descartes’s general strategy in Meditation Two, which is designed to prepare the inference that he actually advances in Meditation Six only. I refer to this strategy as the ‘prejudice strategy’ and suppose that it also encompasses a new version of the ‘die-hard mind argument,’ now grafted in a completely new argumentative structure. 2. NEW PATHS The concerns about the soundness of the ‘die-hard mind argumentD’ are likely the reasons why the ‘simple argument’ for the spirituality of the mind turns into a ‘complex’ one in the Meditations.20 Taking the ‘thinking matter issue’ into account is crucial for the whole architecture of Descartes’s demonstration because only by acknowledging the theoretical possibility of this theory, and simultaneously denying its actual plausibility, can he be assured that the clear and distinct notions of the thought and the bodily nature on which he pivots for demonstrating the real distinction of the mind and body, are not spoiled. In this way, he can sidestep the accusations that were levelled against him after the Discourse (i.e., that of having grounded his inference (E) on a naïve and hasty conception of the mind’s immateriality). In effect, in the ‘complex argument,’ the inference (E), leading towards the immateriality of the mind, is advanced by means of a much more layered and tangled path, one structured around a new opposition. This opposition is that between the “order of perception” (i.e., that knowledge we have about how things appears to us) and the “order of reality” (i.e., the knowledge we have about the way things really are).21 19. This idea forms the basis of Descartes’s usage of the methodic doubt since the Discourse. It is explained quite perspicuously in the Synopsis of the Meditations, where he claims that “although the usefulness of such extensive doubt is not apparent at first sight, its greatest benefit lies in freeing us from all our preconceived opinions” (AT VII, 12; CSM, 9). 20. The new path of the Meditations is acknowledged by most Cartesian scholars, like Kenny 1968: 79-95, Wilson 1978: 44-87; Landucci 2021: 53-83. On this point, see also Guidi 2018: 320-333. 21. This conceptual pair is introduced by Descartes again in the Preface, presenting his arguments against Mersenne and Pollot: “My answer to this objection is that in that passage it was not my intention to make those exclusions in an order corresponding to the actual truth of the matter [in ordine ad ipsam rei veritatem] (which I was not dealing with at that stage) but merely in an order corresponding to my own perception [in ordine ad meam perceptionem]. 188 simone guidi Descartes needs the “order of perception” – “order of reality” duo in order to guarantee the cogito and the subsequent definition of the ego as a ‘thinking thing’ a safe space from the ‘thinking matter issue.’ Indeed, however, the ‘thinking matter’ theory is true or false and the meditator can remain isolated within its own psychological perception and have some kind of certainty about the thought found within. Moreover, and in light of what we recalled above, it is no accident that the ‘complex’ path that Descartes devises for the Meditations points to the distinction between pure intellection and imagination (taking place in Meditation Six), as the vanishing point of the demonstration of the real distinction between the mind and the body.22 It may be analytically resumed in the following points: Order of perception a) in Meditation Two, having demonstrated the existence of the ego, Descartes acknowledges that his knowledge of himself is not sufficiently clear23 and seeks out its possible essence; he excludes anything related to bodies and eventually defines it as a thinking thing (“Thinking? At last I have discovered it – thought; this alone is inseparable from me. I am, I exist – that is certain. But for how long? For as long as I am thinking”);24 b) in Meditation Two, Descartes also acknowledges that he cannot assume the essence of the mind and the bodies since it “may […] be the case that these very things which I am supposing to be nothing, because they are unknown to me, are in reality identical with the ‘I’ of which I am aware”, and at this stage he decided to “make judgements only about things which are known to me”;25 rather, he can describe26 the mind only in terms of psychological certainty (i.e., by introspective analysis, based on a slightly different version of the ‘die-hard mind argument’ [‘die-hard mind argumentM’]).27 Accordingly, he defines the mind as “a thing that doubts, understands, affirms, denies, is willing, is unwilling, and also imagines and has sensory perceptions.”28 This definition comes without the knowledge of what the ultimate, real essence of the substance bearing the activity of thought is; So the sense of the passage was that I was aware of nothing at all that I knew belonged to my essence, except that I was a thinking thing, or a thing possessing within itself the faculty of thinking” (AT VII, 8; CSM II, 7). 22. Starting from this point, Descartes also has to finally renounce the important role he had assigned to imagination in theory of knowledge, particularly in his early philosophy. On imagination in the Regulae and its subsequent dismissal see especially Sepper 1996. 23. See Frankfurt 1970: 154ff. 24. AT VII, 27; CSM II, 18. 25. Ibid. 26. I therefore agree with Frankfurt 1970: 166, who argues that “Descartes propounds sum res cogitans […] only as a description of himself and not as a definition of his essence”. 27. See below, section 2. 28. AT VII, 28; CSM II, 19. descartes and the ‘thinking matter issue’ 189 c) after having shaped an hypothetical notion of the mind and the body through the wax experiment in Meditation Two, Descartes gains (c1) only in Meditation Five an indisputable essence of material things (geometry), known by innate knowledge ensured by (c2) the certainty of evidence (clarity and distinctness) in Meditation Four; even though we do not know whether these material things actually exist, this essence refers to all possible material things, and so also to ‘my’ body, if one exists; From the order of perception to the order of reality d) thanks to (c), in Meditation Six he can demonstrate that the material things hypothesized in (c) are essentially different from the thinking things perceived in (a) and (b), and so are unable to think; he does so by the famous chiliagon mental experiment, by which he proves the real distinction of the pure intellectual activity from the intellectual activity that it carries on with the collaboration of ‘my’ body among the possible bodies in (c), and with imagination as the possible bodily activity appointed with this role in particular; in this way, Descartes gets a clear and distinct idea of thought; Order of reality e) if the essence of the mind is entirely diverse from that of body, then the mind has at least one operation that bodies could not carry out; thus, one can convert the psychological certainty of (b) into an ontological demonstration of the real distinction between the mind and the body, one based on the fact that this distinction is both clear and distinct (thanks to c2) and that God can do everything that I understand clearly and distinctly (Wilson’s “epistemological argument”29); f ) in Meditation Six, Descartes can finally demonstrate that the bodies, really distinct from minds I, are the only cause of perceptions in minds; thus, they are not only possible beings, but also really exist. Hence, in this ‘complex’ version of his demonstration, set out in the Meditations, Descartes only connects indirectly the cogito with the real distinction of the nature30 of 29. See Wilson 1976; 1978a: 162-175; 1978b. 30. In Descartes 1925: 309, Étienne Gilson noted that, in the Discourse, “the demonstration that the soul is a substance entirely distinct from the body is equivalent to the demonstration that the soul is really distinct from the body. The perspective of the Meditations is completely different. A real distinction implies the reality of the things distinguished. If, then, we cast doubt on the existence of the body, it is no longer enough to have proved the existence of thought, or even its complete independence from the body, in order to have proved the real distinction between soul and body; we must also remove the doubt that hangs over the existence of the body by proving the reality of the external world. It is because the two theses are inseparable that Meditation Six is entitled: De rerum materialium existentia, et reali mentis a corpore distinctione” (my translation). As is well-known, Gueroult 1985: II, 52-57 has sharply noted that here Gilson is mistakenly taking ‘essence’ and ‘reality’ as synonyms. In fact, in Meditation Six Descartes demonstrates that the essence of the mind is completely diverse from the essence of the body, regardless of the real existence of the mind (already proven by the cogito) and the body/bodies (proven only in a later stage of Meditation Six). 190 simone guidi mind and body and to the existence of extra-mental, material realities thereafter. More importantly, from the cogito argument in Meditation Two Descartes does not aim to directly derive that the mind that he had proven to exist cannot be corporeal (as he did in the ‘die-hard mind argumentD’), and that the thought experienced ‘from within the mind’ originates from a completely immaterial substance. Remaining within the “order of perception,” and prior to (d) in Meditation Six, the ‘thinking matter theory’ is an alternative that remains plausible, though. This general rearrangement is also the reason why Descartes presented a reworked version of the ‘die-hard mind argumentD,’ which I call the ‘die-hard mind argumentM.’ In Descartes’s new argument, a perception of the mind as something diverse from the body is also immediately available to our knowledge after the cogito. As long as I maintain the assumption that no bodies actually exist, and I am simultaneously certain that I exist, then I can readily rule out any kind of body, albeit in the “order of perception” only, as candidates for the essence of the ego. This inference corresponds to what Descartes argues in Meditation Two right after the cogito argument: what shall I now say that I am, when I am supposing that there is some supremely powerful and, if it is permissible to say so, malicious deceiver, who is deliberately trying to trick me in every way he can? Can I now assert that I possess even the most insignificant of all the attributes which I have just said belong to the nature of a body? I scrutinize them, think about them, go over them again, but nothing suggests itself; it is tiresome and pointless to go through the list once more. But what about the attributes I assigned to the soul? Nutrition or movement? Since now I do not have a body, these are mere fabrications. Sense-perception? This surely does not occur without a body, and besides, when asleep I have appeared to perceive through the senses many things which I afterwards realized I did not perceive through the senses at all.31 Yet, what actually distinguishes the argument presented in the Meditations from the ‘die-hard mind argumentD’ is that the ‘die-hard mind argumentM’ applies only to the “order of perception” (i.e., on the mental perception of mind and body, and not on the essence of the mind and the body in themselves).32 Hence, whereas it structures a specific perception of the mind as non-corporeal, the argument does not claim to totally rule out the ‘thinking matter’ hypothesis right after the cogito, and regards it as still 31. AT VII, 26-27; CSM II, 18. 32. See Di Bella 1997: 78: “in 1637, the reductio subsequent to the cogito directly granted the following conclusions: a) I am a substance whose essence is thinking; b) this substance is better known that the body; c) it is really distinct from the body. The Synopsis [in the Meditations] enumerates between the results of Meditation Two only (b), i.e. that the mind is better known than the body, and (c’), the distinction between the notion of mind and that of body; and it emphasizes that it is only up to Meditation Six to establish the real distinction” (my translation). As Frankfurt 1970: 163, notes, Descartes’ conclusion “in the Second Meditation that he is a thinking thing means only that thought is the one characteristic he can justifiably ascribe to himself at the current stage of his inquiry”. descartes and the ‘thinking matter issue’ 191 being possible, up to Meditation Six.33 Let us consider what Descartes clearly claims in Meditation Four: now, besides the knowledge that I exist, in so far as I am a thinking thing, an idea of corporeal nature comes into my mind; and I happen to be in doubt as to whether the thinking nature which is in me, or rather which I am, is distinct from this corporeal nature or identical with it. I am making the further supposition that my intellect has not yet come upon any persuasive reason in favour of one alternative rather than the other.34 Moreover, contrary to what most part of Cartesian scholarship affirms,35 the meditator does not form a clear and distinct notion of the mind in the ‘die-hard mind argumentM’ of Meditation Two, but rather she/he simply endeavors to push her/his psychological perception36 of the mind and the body to the clearer and more distinct level as much as possible.37 In effect, Descartes seems willing to admit that the notions of the mind and the body shaped in Meditation Two are distinct perceptions, but he is quite reluctant to say that they are the clear and distinct perceptions of their essences, required for a true real distinction. Whereas I can grasp (for instance, from the famous wax experiment) the fact that thought and extension are (whatever their respective natures are) different things, I do not have a clear understanding of their essence before Meditation Five (bodies (c1)) and Six (mind (d));38 and, similarly, I cannot use clear and distinct per33. Paraphrasing Kenny (1968: 86), one could say that Descartes passes from “I am known for certain to have no property other that the thought” (Discourse) to “I am not known for certain to have any property other than thought” (Meditation Two). 34. AT VII, 59; CSM II, 41. 35. For instance, Gueroult 1985: I, 37; Wilson 1976: 5 and 1978a: 43, 67. An opposite view is Frankfurt’s (1970). 36. In Meditation Two, Descartes defines this perception as a mental inspection which can be more or less clear and distinct depending on the level of attention we put on it: “The perception I have of it [the wax] is a case not of vision or touch or imagination – nor has it ever been, despite previous appearances – but of purely mental scrutiny (inspectio); and this can be imperfect and confused, as it was before, or clear and distinct as it is now, depending on how carefully I concentrate on what the wax consists in” (AT VII, 31; CMS II, 21, my emphasis). Hence Descartes associates this clearness and distinction with the psychological attention and concentration that the mind gets by using the methodic doubt, as he will argue in the Replies (see section 4 below). So here he is simply claiming that in Meditation Two the mind and the body are perceived more clearly and distinctly than before, and not that we get a truly clear and distinct notion of them, as the cogito intuition is. 37. See again the Synopsis, where Descartes literally claims that in Meditation Two is formed a notion of the mind “as clear as possible [ut quam maxime] and also […] quite distinct from the notion of the body” (AT VII, 13; CSM, 12). I truly thank the referees for their useful remarks about this point of my analysis. 38. Furthermore, as Wilson 1976: 9-10 herself has noted, Descartes likely distinguished between conceiving something distinctly and conceiving something distinctly and as a complete thing. Only the second way brings us to a conception of something really distinct, whereas mere distinction is the formal distinction suggested by Caterus: “It is sufficient for this kind of distinction that one thing be conceived distinctly and separately from another by an abstrac- 192 simone guidi ceptions as rules for necessarily true judgments before Meditation Four. No matter how hard she/he tries, the meditator cannot get any clear and distinct notion of the thought from the definition of the ego as an existing thinking thing, until she/he first has a clear and distinct idea of the body. First of all, they cannot infer these two notions until the ‘thinking matter theory’ is totally ruled out. However, this is only done in Meditation Six, and after having distinguished between the pure intellection, performed without any help from the body, and intellection as applied to the body (i.e., imagination). Therefore, whereas Meditation Two investigates the possibly distinct notions of the mind and the body based on their psychological perception, only Meditation Six can affirm the real distinctness and clearness of these notions.39 So, the ‘die-hard mind argumentM’ does not rely on a really clear and distinct idea of the mind residual after the cogito, but instead relies on the psychological certainty the mind has about itself as a ‘thinking thing’ (whatever this means). Its structure is therefore: D1: I can doubt that I, who am thinking, have a body; D2: I cannot doubt that I, who am thinking, exist [i.e., the cogito]; E: Ergo, I, who exist and am thinking and doubting about the bodies, cannot admit that I am a body. I, who am thinking and doubting, can only think of myself as a thinking thing.40 This is enough to allow Descartes to start Meditation Three with a tiny, but crucial, amount of success. While he has no clear and distinct perception of what the mind and the body are in re, he finally has a model for the clear and distinct perception in general: “I am certain that I am a thinking thing”41 – whatever a ‘thinking thing’ is (i.e., even if I do not have a clear notion of the nature of thinking so I cannot really say whether I am or not ‘a thinking thing only’). As far as I can determine, this version estion of the intellect which conceives the thing inadequately” (AT VII, 120; CSM II, 85-86). Instead, the complete understanding is necessarily related with things really distinct from other things for Descartes (AT VII, 121; CSM II, 86). Until we have a clear and complete conception of the mind and the body (which we cannot have before Meditation Six), we are left with a distinct conception of it, which might yet point to just a formal or rational distinction between the two res, not a real one. On this point see also Kenny 1968: 89-95. 39. The aim of Meditation Two is not, indeed, to discuss the nature of the mind and the body understood completely, but to stress that the mind can be known better than the body and that its knowledge is more distinct at that point than the knowledge of the body. This is, in effect, what Descartes claims in the Third Replies (to Hobbes): “[in Meditation Two] I was not dealing […] with the formal concept [ratio formalis] of the mind or even with that of the body” (AT VII, 175; CSM II 124). Nonetheless, in the title of Meditation Two (De natura mentis humanae; quod ipsa sit notior quam corpus), what is claimed to be known better than the body is not the nature of the human mind, but the human mind itself. See Landucci 2001: 5-7. 40. As Kenny 1968: 87 noted, in Meditation Two “what is being asserted is that I, qua known for certain, am not any bodily entity”. And this restriction finally makes Descartes’s ‘die-hard mind argument’ work, since, as Kenny argues, “For I know for certain that I am identical with a body, then I cannot consistently suppose all bodies not to exist without supposing myself not to exist”. However, Descartes cannot say in Meditation Two “that thinking is his essence” and he must settle for saying “that it is his only inseparable property” (92). 41. AT VII, 35; CSM II, 24. descartes and the ‘thinking matter issue’ 193 capes Malcom’s and Pollot’s arguments against I in the previous version of the ‘die-hard mind argument’: from D1, Descartes is not inferring that he is not a body, but only that he cannot admit he is a body while simultaneously doubting the existence of the bodies. 3. OLD PREJUDICES Descartes’s whole strategy from Meditation Two to Meditation Six is, hence, that of walking the tightrope connecting the order of perception and that of reality. This allows him to use doubt to leave the judgment suspended concerning the plausibility of the ‘thinking matter theory,’ until such a time as he has sufficient arguments to get rid of this hypothesis. Namely, until the moment when, after Meditation Four and Five, he can rely on the ‘clear and distinct’ principle and on a sufficiently clear notion of the body by which a distinction from the thought can be performed. Only then can the ‘thinking matter theory’ be brought out in the form of the opposition between pure intellection and imagination and can be definitively wiped out. These movements seem to be part of a wider strategy that Descartes covertly advances from Meditation Two onwards, and which I have referred to as the ‘prejudice strategy’. The ‘prejudice strategy’ is connected to what Étienne Gilson, in more critical terms, has dubbed the “Cartesian paradox.”42 It asserts that the issue of ‘thinking matter’ is a false problem stemming from the erroneous notions in which we understood the mind and the body prior to the methodic doubt, in the condition that Richard Kennington and John Cottingham dubbed ‘pre-philosophical experience’.43 The core of this theory is that we always and necessarily have had clear and distinct notions of both the mind and the body, which one can intuitively grasp when considering the mind. These correspond to real things and are, thus, also able to validate the ‘die-hard mind argumentM’ on the order of reality. Hence, what is to be demonstrated is not that these clear and distinct notions correspond to real things, but rather that we really have these notions, such that we can rely on them. Now, on the one hand, this strategy coincides with Descartes’ famous strategy of the validation of the ‘clear and distinct’ principle in Meditation Four and Five; however, and on the other hand, it replies to a quite naïve, albeit philosophically significant, question that would be addressed to Descartes in the Sixth Set of Objections: if the mind 42. Gilson 1930: 225: “the metaphysics of the Meditations […], end up with what one can call the Cartesian paradox. The conclusion toward which it leads as a whole is the real distinction of soul and body. This distinction first supposes that we have distinct ideas of soul and body, then that souls really exist, and finally that bodies really exist. And since we cannot prove the real existence of bodies except by relying on what is confused and involuntary in sensible knowledge, we must suppose a kind of violence inflicted on thought from the outside, a kind of confusion of natures that explains the confusion of knowledge. As a result, the Cartesian proof for the existence of an external world seems to imply as an essential element the union of soul and body. But since the proof of existence has no other end than to establish the real distinction between soul and body, we must go so far as to assert that the proof of their distinction relies on the fact of their union” (translation by Roger Ariew in Gueroult 1985: 276, n. 13). 43. Kennington 1972: 87-88, 96-99, 115 and Cottingham 1986: 77. 194 simone guidi and the body are different, then why do we experience them as constantly mingled? Why does it seem quite reasonable, as Pollot noted, that what affects the brain also affects the mind? The ‘prejudice strategy’ also ascribes to the senses – and more specifically to our tendency to take them too seriously and make judgment about perception44 – the only cause of these ideas that, for Descartes, obscured our clear and distinct perception.45 Famously, this theory is presented by Descartes only in Meditation Six as part of a final reassessment of the “teaching of nature”46 after the demonstrations of the real distinction of the mind and the body and of the existence of bodies: I see that I have been in the habit of misusing the order of nature. For the proper purpose of the sensory perceptions given me by nature is simply to inform the mind of what is beneficial or harmful for the composite of which the mind is a part; and to this extent they are sufficiently clear and distinct. But I misuse them by treating them as reliable touchstones for immediate judgements about the essential nature of the bodies located outside us; yet this is an area where they provide only very obscure information.47 Sense-based judgments are, therefore, responsible for misleading the mind and “misusing” the real order of nature, and this is the only cause of the hypothesis about the ‘thinking matter.’ Why does Descartes unleash this argument only in Meditation Six, after having demonstrated what he wanted to demonstrate, though? The reply is once again quite simple. Due to its structural reference to the senses, the ‘prejudice strategy’ is not a theoretical argument, one that can be employed directly in a demonstration. Instead, it is an anthropological thesis and is part of a wider anthropological view that Descartes wants to put to the test and demonstrate in the Meditations. He simply cannot contend that the ‘thinking matter issue’ is just a prejudice until he has first shown that we have clear, distinct and reliable notions of both the mind and the body. Hence, he can 44. See AT VII, 82; CSM II, 56: “There are […] many other things which I may appear to have been taught by nature, but which in reality I acquired not from nature but from the habit of making ill-considered judgements; and it is therefore quite possible that there are false”. 45. Cottingham 1986: 87, keenly notes that this is the opposition between ‘me’ qua thinking thing and ‘me’ qua compound of mind and body: “firstly I possess clear and distinct perceptions of the natural light, which are attributable to me qua thinking thing, and which tell me that I am a non-corporeal, purely thinking substance; and secondly I have ‘natural’ feelings and sensations […] which are attributable to me qua compound of mind and body, and which tell me that I am (at least partly) corporeal”. 46. See again, on this notion, Kennington 1972 (who contrasts ‘practical’ with ‘theoretical’ teaching of nature’: 99) and Cottingham 1986 (contrasting “my nature” alone and “my nature” as “endowed with a faculty of reason”, which is a reliable guide to the truth: 82). As for the aftermath of the Meditations, and particularly the Passions of the soul, see Rethy 2000 (stressing the different notions of ‘institution of nature’ and ‘teaching’ or ‘dictate’ of nature: 666-667). 47. AT VII, 83; CSM II, 57-58. descartes and the ‘thinking matter issue’ 195 reveal it only in Meditation Six, when the puzzle has already and finally been solved.48 However, I maintain that the ‘prejudice strategy’ covertly structures the whole Meditation Two as a leading hypothesis and that Descartes constantly keeps it in his mind. My idea is that the whole of Meditation Two is built upon the notion that the only reason that we have to raise the ‘thinking matter issue’ is the confusion caused by the “teaching of nature” and because of our habit of relying on the senses. Hence, Descartes claims, if we had not fallen in the obscurity of the senses, then we would have always had the same intuition of our nature as claimed by the ‘die-hard mind argumentD’ in the Discourse. To Descartes, the 1637 inference is hence still there, but its fire burns under the ashes of the confusion that initially gave rise to the ‘thinking matter’ issue. Thereby, if we are able to amend this confusion, then we are also able to have a direct intuition of our own nature. Now, while prior to Meditation Six we cannot rule out the ‘thinking matter theory’ on the level of the “order of reality,” thanks to the ‘die-hard mind argumentM’ we are at least able to achieve a quite distinct and quasi-clear (but not clear and distinct) intuition of our nature; this works perfectly in the “order of perception” at least. Indeed, this intuition is able to defeat the ‘thinking matter theory’ as far as our perception goes, thereby reducing it just to the hypothesis that, until I am not sure that God exists and I can rely on my clear and distinct perceptions, I cannot trust in what the ‘die-hard mind argumentM’ clearly suggests. Put more simply, the ‘die-hard mind argumentM’ is able to counterpose the ‘thinking matter issue’ with the principle of clarity and distinctness. Descartes’ principle goes as follows, where CD means ‘clear and distinct’ and TMT the ‘thinking matter theory’: CD → ¬ TMT TMT → ¬ CD Nonetheless, this seems to be exactly what Descartes claims in the Synopsis of his masterpiece, where he very clearly stressed the new path adopted in the Meditations and the role played by what I call the ‘die-hard mind argumentM.’49 However, in order to find 48. As noticed by Kennington 1972: 88, “Cartesian doubt in Meditations I-II is presented as the conflict of the natural attitude (the ‘teaching of nature’) and scientific reason (‘the light of nature’)”. Hence, the function of Cartesian doubt is “to suspend” the ‘teaching of nature’ “so that natural reason can attain the standpoint of scientific intellect, or the separation of mind […] from the world” (100). On the other hand, as mentioned, Descartes himself stresses in the Synopsis that the “greatest benefit” of “such extensive doubt” “lies in freeing us from all our preconceived opinions, and providing the easiest route by which the mind may be led away from the senses” (AT VII, 9; CSM II, 12). 49. “In the Second Meditation, the mind uses its own freedom and supposes the non-existence of all the things about whose existence it can have even the slightest doubt; and in so doing the mind notices that it is impossible that it should not itself exist during this time. This exercise is also of the greatest benefit, since it enables the mind to distinguish without difficulty what belongs to itself, i.e. to an intellectual nature, from what belongs to the body. But since some people may perhaps expect arguments for the immortality of the soul in this section, I think they should be warned here and now that I have tried not to put down anything which I could not precisely demonstrate. Hence the only order which I could follow was that normally employed by 196 simone guidi a clear formulation of what I have argued about, concerning the presence of the ‘prejudice strategy’ in Meditation Two, I will first have to delve into Descartes’s replies to his objectors; particularly, he will have to respond to Mersenne and Gassendi, who attack him on the point of the ‘thinking matter issue.’ This is what I intend to undertake in the following section. 4. ATTACKING AND DEFENDING Despite the fact that Meditation Six announces in its title that it concerns “the existence of material things, and the real distinction between mind and body,” Descartes’s objectors would attack the problem of ‘thinking matter’ referring specifically to Meditation Two. In effect, both Mersenne and Gassendi have sharply grasped (perhaps from the Synopsis) that Meditation Two, more than Meditation Six, is the crucial place in which the ‘thinking matter theory’ is reduced to problem of clarity and distinctness over and against the general backdrop of the ‘prejudice strategy.’ Let us consider how Mersenne questions the ‘die-hard mind argumentM’ of Meditation Two in his Second Set of Objections: may we remind you that your vigorous rejection of the images of all bodies as delusive was not something you actually and really carried through, but was merely a fiction of the mind, enabling you to draw the conclusion that you were exclusively a thinking thing. We point this out in case you should perhaps suppose that it is possible to go on to draw the conclusion that you are in fact nothing more than a mind, or thought, or a thinking thing. And we make the point solely in connection with the first two Meditations, in which you clearly show that, if nothing else, it is certain that you, who are thinking, exist. But let us pause a little here. The position so far is that you recognize that you are a thinking thing, but you do not know what this thinking thing is. What if it turned out to be a body which, by its various motions and encounters, produces what we call thought? Although you think you have ruled out every kind of body, you could have been mistaken here, since you did not exclude yourself, and you may be a body. How do you demonstrate that a body is incapable of thinking, or that corporeal motions are not in fact thought? The whole system of your body, which you think you have geometers, namely to set out all the premises on which a desired proposition depends, before drawing any conclusions about it. Now the first and most important prerequisite for knowledge of the immortality of the soul is for us to form a concept of the soul which is as perspicuous [I have replaced the misleading translation of CSM (“clear”) for a more literal one of the original Latin perspicuum de ea conceptum] as possible and is also quite distinct from every concept of body; and that is just what has been done in this section. A further requirement is that we should know that everything that we clearly and distinctly understand is true in a way which corresponds exactly to our understanding of it; but it was not possible to prove this before the Fourth Meditation. In addition we need to have a distinct concept of corporeal nature, and this is developed partly in the Second Meditation itself, and partly in the Fifth and Sixth Meditations” (AT VII, 12-13; CSM II, 9; my emphasis). The Synopsis dates back to December 1640-January 1641 and was sent by Descartes to Mersenne as an addendum to the Meditations aimed chiefly at orienting the reader (see Descartes to Mersenne, AT III, 272). descartes and the ‘thinking matter issue’ 197 excluded, or else some of its parts – for example those which make up the brain – may combine to produce the motions which we call thoughts. You say ‘I am a thinking thing’; but how do you know that you are not corporeal motion, or a body which is in motion?50 The core of Mersenne’s critique is quite simple: the ‘thinking thing’ that Descartes identifies after the cogito might be something with a bodily nature. Indeed, how might I be sure that, since I think and so I am a thing that thinks, my thought is essentially immaterial, though? Am I only an immaterial substance? Mersenne (along with Léonor La Barde)51 would reiterate the same attack, even more openly, in the Sixth Set of Objections.52 Pierre Gassendi would also level a similar critique53 in his Fifth Set of Objections: you reach the conclusion that thinking belongs to you. This must be accepted, but it remains for you to prove that the power of thought is something so far beyond the nature of a body that neither a vapour nor any other mobile, pure and rarefied body can be organized in such a way as would make it capable of thought. […] You will also have to prove that this solid body of yours contributes nothing whatever to your thought (for you have never been without it, and have so far never had any thoughts when separated from it). You will thus have to prove that you think independently of the body in such a way that you can never be hampered by it or disturbed by the foul and dense vapours or fumes which from time to time have such a bad effect on the brain.54 50. AT VII, 122-123; CSM II, 87-88. 51. As proven by the letter to Mersenne, June 23, 1641, AT III, 385. 52. AT VII, 420; CSM II, 283: “However much we ponder on the question of whether the idea of our mind (or a human mind), i.e. our knowledge and perception of it, contains anything corporeal, we cannot go so far as to assert that what we call thought cannot in any way belong to a body subject to some sort of motion. For since we see that there are some bodies that do not think, and others, namely human bodies and perhaps those of the brutes, which do think, will not you yourself convict us of sophistry and of making rash judgements if we infer from this that there are no bodies that think? We can hardly doubt that we would deserve your lasting ridicule if it was we who had originally devised this argument from ideas to establish the nature of the mind and the existence of God, and you had then condemned it by using your method of analysis. But you seem to be so preoccupied and prepossessed by this method that you seem to have dulled your mind with it, so that you are no longer free to see that the individual properties or operations of the soul which you find in yourself depend upon corporeal motions”. 53. It seems to me that Gassendi’s attack is waged from a slightly different perspective that Mersenne’s. Unfortunately, I do not have the space to dwell on this difference. One peculiar point of Gassendi’s critique to Descartes is, however, that he challenges the ‘clear and distinct’ principle (see LoLordo 2005). Accordingly, he questions the entirety of the ‘prejudice strategy.’ See also LoLordo 2019: sections 3 and 6, and 2023: 201-206. 54. AT VII, 262; CSM II, 183. And, attacking on Meditation Six: “why should I spend any more time on this when the onus is on you to prove that you are an unextended and hence incorporeal thing? You will hardly, I think, support your claim by pointing out that man is commonly said to consist of a body and a rational soul – as if it followed from the fact that one part is said to be a body that we must not call the other part a body. If you did take this line, you would give us the chance to make a distinction and say that man consists of two kinds of 198 simone guidi Both of these remarks call back into question the ‘thinking matter’ issue, thereby prompting Descartes to overtly address the problem in these terms. His replies constitute a partial reissue of Meditation Two, whose aims and intricacies now appear more clearly outlined, revealing the underlying presence of the ‘prejudice strategy.’ In his reply to Mersenne, Descartes restates that at that stage (b) he “was not yet asking whether the mind is distinct from the body, but was merely examining those of its properties of which [he] can have certain and evident knowledge.”55 However, he proceed by also elucidating the view that Meditation Two aimed, in particular, to show that the mind (as effectively announced in the title of Meditation Two) is “better known than the body, when it is considered apart from the mind,”56 and, more crucially, that Meditation Two aimed to enable the meditator to discern (on the “order of perception”) the properties of the mind from those of the bodies, even if those qualities are (on the “order of reality”) always experienced as intertwined and muddled: I thought I would be doing something worthwhile if I explained how the properties or qualities of the mind are to be distinguished from the qualities of the body. Admittedly, many people had previously said that in order to understand metaphysical matters the mind must be drawn away from the senses; but no one, so far as I know, had shown how this could be done. The correct, and in my view unique, method of achieving this is contained in my Second Meditation.57 According to Descartes’s reply, the introspective analysis of Meditation Two after the cogito, not only aims to provide a close description of the mind ‘from within.’ Alongside the methodic doubt, it also serves at psychologically disconnecting the mind from the body, thereby breaking up the confused everyday experience that we have as human mind-body compounds.58 This is why, Descartes argues, even though we are still unable to prove the real distinction of material and immaterial things, the ‘die-hard mind argumentM’ can refine our ideas up to the point that we experience our mind as if it was disembodied. Accordingly, we can be psychologically assured that it can be essentially different from the body. Yet, this whole process occurs in direct contrast to what we usually experience and in compliance with ‘the prejudice strategy.’ In effect, Descartes reasons analytical- body, a solid one and a rarefied one, the common name ‘body’ being retained by the former, while the latter is called the ‘soul’. I will pass over the fact that the same could then be said of the other animals to whom you are not prepared to grant a mind like your own; they would then be lucky indeed, since on your account they would at least have a soul! So when you conclude that it is certain that you are really distinct from your body, you see that I will grant you this conclusion, but will not therefore grant that you are incorporeal, as opposed to being a kind of very rarefied body distinct from your more solid body” (AT VII, 342; CSM II, 237). 55. AT VII, 129; CSM II, 93 (my emphasis). 56. AT VII, 130; CSM II, 94. 57. AT VII, 131; CSM II, 94. 58. On this point see Guidi 2018: 259-311. descartes and the ‘thinking matter issue’ 199 ly,59 and assumes that the ‘die-hard mind argumentM’ is simultaneously an argument and an argument for the argument itself.60 On the one hand, apart from methodic doubt, it should persuade us that we really had good reasons to suspect our naïve idea that the mind and the body somehow overlap. Since on the “order of perception” we can shape through doubt certain distinct and quasi-clear notions of the thought and the body, even though the ‘thinking matter theory’ still remain possible (and prevents us from claiming that we have clear and distinct notions thereof and that they are really distinct), these provisional notions might actually coincide with genuine clear and distinct notions. On the other hand, it allows the meditator to hypothesize that the very origin of the misleading idea of ‘thinking matter’ is based on prejudice. Indeed, if we subscribe to the hypothesis put forth through the ‘die-hard mind argumentM,’ then we see that there is no positive reason to formulate the ‘thinking matter theory.’ Let us read what he replies to the Second Set of Objections: 59. As Descartes famously acknowledges in the Second Replies, the whole demonstrative path of the Meditations is structured after the method of analysis in ancient geometry. For Descartes, “analysis shows the true way by means of which the thing in question was discovered methodically and as it were a priori, so that if the reader is willing to follow it and give sufficient attention to all the points, he will make the thing his own and understand it just as perfectly as if he had discovered it for himself” (AT VII, 155; CSM II, 110). On this point see in particular the enlightening papers by Hintikka (1978) and Timmermans (1999), stressing that Descartes’s usage of the analytic method he takes from geometry points especially at re-constructing “interdependent elements” (Hintikka 1978: 81) or “correspondences, order, or relations between different terms” (Timmermans 1999: 444). 60. As stressed by in particular by Cellucci 2013: 55, “The analytic method is the method according to which, to solve a problem, one looks for some hypothesis that is a sufficient condition for solving it. The hypothesis is obtained from the problem, and possibly other data already available, by some non-deductive rule, and must be plausible […]. But the hypothesis is in its turn a problem that must be solved, and is solved in the same way. That is, one looks for another hypothesis that is a sufficient condition for solving the problem posed by the previous hypothesis, it is obtained from the latter, and possibly other data already available, by some non-deductive rule, and must be plausible. And so on, ad infinitum”. Cellucci’s definition relates to the original formulation laid down by Plato 2013: 65ff., which for Curley 1986: 157 is Descartes’s analytic method. It seems to me (in accordance with most Cartesian scholars) that, even though in the Meditations only the analytic method is employed (AT VII, 156; CSM II, 111), Descartes’s geometrical method is inspired by Pappus’s ‘theorematic’ version of the ‘analysis-synthesis method’. Pappus’s usage of ‘analysis’ is exposed in his Mathematical Collection: “analysis is the way from what is sought – as if it were admitted – through its concomitants in order to something admitted in synthesis. For in analysis we suppose that which is sought to be already done, and we inquire from what it results, and again what is the antecedent of the latter, until we on our backward way light upon something already known and being first in order. And we call such a method analysis, as being a solution backwards” (trans. from Hintikka & Remes 1974: 8-9). I maintain that this reading is allowed by a keen remark by Gaukroger 1989: 77, who notes that in Pappus’s ‘analysis-synthesis method’, where it comest to negative results (i.e. in cases of demonstrations structured as reductio ad absurdum), there is no place for synthesis. In effect, it seems that the entire Meditations are a reductio ad absurdum started from the paradoxical refusal of the true God (see Guidi 2024). 200 simone guidi If there are those who claim that they do not have distinct ideas of mind and body, I can only ask them to pay careful attention to the contents of the Second Meditation. If, as may well be the case, they take the view that the formation of thoughts is due to the combined activity of parts of the brain, they should realize that this view is not based on any positive argument, but has simply arisen from the fact that, in the first place, they have never had the experience of being without a body and that, in the second place, they have frequently been obstructed by the body in their operations. It is just as if someone had had his legs permanently shackled from infancy: he would think the shackles were part of his body and that he needed them for walking.61 Descartes argues two fundamental elements of what we dubbed the ‘prejudice strategy’ in this passage. He stresses that the notion of a material thing (in this case, the brain) which is thought of as being able to think, is just a goat-stag, stemming from the mingled experience of the nature of thought and extension offered to the mind by the senses, within its composition with the body. More importantly, though, he also points out that such a hypothesis is totally nonsensical, lacking any sound argument to substantiate it. Indeed, the only reason to entertain the ‘thinking matter’ theory lies in the mistaken perception of the essence of material things, which deceives even the principle of evidence leading the mind in all its true inferences. This is why, replying to Gassendi, Descartes claims that he not only temporarily assumed that he had not a body in Meditation Two, but, based on this psychological perception and the ‘die-hard mind argumentM,’ he even assumed that the mind is not a body: I showed that it can be supposed that there is no wind or any other body in the world, yet nonetheless everything which enables me to recognize myself as a thinking thing still remains. Hence all your subsequent questions as to whether I might not still be a wind or occupy space or be in motion in several ways, and so on, are so fatuous as to need no reply. There is no more force in your next question as to why, if I am a rarefied body, I cannot be nourished, and so on. For I deny that I am a body.62 In a later passage of his reply to Gassendi, Descartes sets out his whole position even more effectively. While Gassendi called attention to the ‘thinking matter issue,’ as a good reason to suspect of the ‘die-hard mind argumentM.’ Descartes reaffirms that this theory can be easily knocked out by methodic doubt and by not accepting anything that is unproven. Moreover, once we are safe within the “order of perception,” there is no good reason to think that the mind might be a body: you should realize that in order to philosophize correctly there is no need for us to prove the falsity of everything which we do not admit because we do not know whether or not it is true. We simply have to take great care not to admit anything as true when we cannot prove it to be so. Hence, when I discover that I 61. AT VII, 133; CSM II, 95-96. 62. AT VII, 352-353; CSM II, 244 (my emphasis). descartes and the ‘thinking matter issue’ 201 am a thinking substance, and form a clear and distinct concept of this thinking substance that contains none of the things that belong to the concept of corporeal substance, this is quite sufficient to enable me to assert that I, in so far as I know myself, am nothing other than a thinking thing. This is all that I asserted in the Second Meditation, which is what we are dealing with here. I did not have to admit that this thinking substance was some mobile, pure and rarefied body, since I had no convincing reason for believing this. If you have such a reason, it is your job to explain it; you should not demand that I prove the falsity of something which I refused to accept precisely because I had no knowledge of it.63 In the first part of this response, Descartes establishes that he could not defeat the ‘thinking matter theory’ by directly denying that the body is able to produce thought in Meditation Two. Therefore, he simply sidestepped it by using the methodic doubt to suspend the judgment about the “order of reality” and to lock up the whole demonstration within the “order of perception” (i.e., “in so far as I know myself”). Therefore, using the ‘die-hard mind argumentM’ he could shape an idea of the mind and the body which (‘prejudice strategy’) is supposed to correspond with the clear and distinct idea we will have in Meditation Six, when (‘prejudice strategy’) we will demonstrate (and not just assume) that the ‘thinking matter theory’ was nothing more than a false problem. In this way, Descartes has just subordinated the whole issue to the problem of the validation of the ‘clear and distinct’ principle, thereby postponing it to the moment when it he would have all the pawns necessary to move and checkmate against the ‘thinking matter issue’ on his chessboards.64 5. INFANCY AND OBSCURITY As I mentioned, behind these theoretical moves, Descartes conceals a remarkable anthropological explanation about the formation of the ‘thinking matter theory’ from 63. AT VII, 354-355; CSM II, 245-246 (my emphasis). 64. The second part of Descartes’s reply seems, nonetheless, quite ambiguous and at odds with some other passages of the Meditations. Descartes claims that the ideas of the mind and the body that he shaped in Meditation Two are “clear and distinct” and that he simply did not consider the ‘thinking matter theory’ “because [he] had no knowledge of it”. Yet, these claims would appear clearer when paying sufficient attention to two elements. On the one hand, he refers to the “clear and distinct” ideas of Meditation Two within the restriction that he sets to the “order of perception” (“in so far as I know myself”). As we have argued, though the meditator is not able to have genuinely clear and distinct ideas about how the mind and the body are, it can have clear and distinct ideas about how the mind and the body appear. On the other hand, Descartes speaks in the first person here, but refers to the narrative self of the Meditations. The meditator did not have any convincing reason to put forward the hypothesis of ‘thinking matter,’ and this is why the ‘thinking matter theory’ is presented only in the guise of sneaky sentences like “it may […] be the case that these very things which I am supposing to be nothing, because they are unknown to me, are in reality identical with the ‘I’ of which I am aware.” This does not exclude, and actually even proves, that the whole narrative of Meditation Two, including the ignorance of the meditator with respect to the ‘thinking matter theory,’ is completely arranged by Descartes according to the general strategy of the ‘prejudice strategy’. 202 simone guidi sensory experience. However, he could only hint at it in the Meditations due to the specific demonstrative approach to which he was committed, and he must settle for subtly following it. In effect, in the anamnestic parts of Meditation Two and Meditation Six,65 Descartes appealed to a quite enigmatic “teaching of nature,”66 which he defined as “a spontaneous impulse [that] leads me to believe” certain things, contrasting with the “truth [that] has been revealed to me by some natural light.”67 Accordingly, in Meditation Two and Six, he set out the idea that the mind, in the state of unity with the body, is led to think as if it was one thing with it, against what is evident and true by natural light (let us call that ‘spontaneous impulse theory’).68 This “impulse” is the only cause of the prejudice openly mentioned in the Meditations. 69 However, Descartes already sketched a more accurate theory in his previous writings, one which he will resort to in the Replies. In the Meditations, he probably presented the ‘spontaneous impulse theory’ as a substitute for his genuine one, which he could not bring forth before the second half of Meditation Six, given that it is entirely grounded on the dualism he aimed to demonstrate. The ‘spontaneous impulse theory,’ by contrast, fit quite well with the structural ideal of the Meditations, that of advancing by analysis of mental contents alone. This may be why the core text of the Meditations missed a clear explanation of the causal factor that shaped this ‘second nature’ of the mind, thereby hiding its clearness in its very ‘first nature’ and introducing this “impulse” in it. This process is presented by Descartes in his reply to the authors of the Appendix in the Sixth Set of Objections who addressed him this particular problem nevertheless: We perceive very well that three and two make five and that if you take equals from equals the remainders will be equal; we are convinced of these and numerous other matters, just as you find yourself to be. But why are we not similarly convinced on the basis of your ideas, or our own, that the soul of man is distinct from the body […]?70 Here the objector (probably La Barde) not only sharply noted that Descartes’s ‘prejudice strategy’ lies under the ‘die-hard mind argumentM.’ He also pointed out an important 65. See for Meditation Two AT VII, 25-26; CSM II, 17-18. See for Meditation Six AT VII, 74-77; CSM, 51-54. 66. For instance, AT VII, 76; CSM II, 53. See again Kennington 1972; Cottingham 1986; Rethy 2000. 67. AT VII, 38; CSM II, 26-27. On this point see especially Cottingham 1986: 82-83. 68. See again Cottingham 1986, who speaks of a “striking gap between the Cartesian clear and distinct perception of the outer world […] and our ordinary experience of it” (85) and contrasts the “voice of nature” “as reason” (i.e., the ‘natural light’) and the “voice of nature” “as experience” (based on the union of mind and body). 69. As noted in particular by Kennington 1972 (with the notion of ‘practical teaching of nature’), and Rehty 2000, the human nature as a compound of mind and body is entirely dominated by the logic of usefulness, and this is what is ultimately ‘taught’ by nature and the ‘impulse’. 70. AT VII, 421; CSM II, 283. descartes and the ‘thinking matter issue’ 203 possible criticality in Descartes’s ‘spontaneous impulse theory,’ thereby also reflecting on the level of demonstration. Indeed, if the different natures of the mind and the body are evident things, then why does the mind need a process of clarification to see the real distinction of the mind and the body? It should, rather, have immediate and natural psychological certainty thereof (i.e., should not occur), much like it has about mathematical truths, which are never subject to prejudice. The fact that we have here two items of the same class (clear and distinct things) but some are immediately self-evident (i.e., mathematical truths) while others still (i.e., the real distinction of mind and body) need further clarification, prompts us to suspect that the latter are not elements of the same class as the former. Moreover, linking his whole demonstration to an anthropological assertion about the capability of the human mind, to achieve clear and distinct ideas, Descartes now has to reaffirm that the human compound is not delusional by its own nature. This lack of evidence is not a stable, natural feature of the human mind-body composition. These observations finally force Descartes to tell the whole story behind his ‘prejudice strategy’ and to reveal one of his most important premises. He presents a theory of childhood that he mentioned in the World71 and in the Discourse previously,72 and which he did not expose in the Meditations (save for some hints in Meditation Six). Childhood is the actual and crucial time at which the confused experience is shaped and impressed in the mind, along with a number of misjudgments; these are then further confirmed by everyday experience. This is the confusion upon which the very idea of a possible mind-body, thought-matter identity ultimately relies, until the point at which one dispels it by proper meditation: From infancy I had made a variety of judgements about physical things in so far as they contributed to preserving the life which I was embarking on; and subsequently I retained the same opinions I had originally formed of these things. But at that age the mind employed the bodily organs less correctly than it now does, and was more firmly attached to them; hence it had no thoughts apart from them and perceived things only in a confused manner. Although it was aware of its own nature and had within itself an idea of thought as well as an idea of extension, it never exercised its intellect on anything without at the same time picturing something in the imagination. It therefore took thought and extension to be one and the same thing, and referred to the body all the notions which it had concerning things related to the intellect.73 71. AT XI, 17; CSM I, 85. 72. AT VI, 13; CSM I, 117. This theory of childhood would become a structural part of Descartes’s philosophical arsenal after the Meditations, and was proposed several times in his subsequent writings and letters. See, for instance, the Principia II, 26 (AT VIII-1, 54; CSM I, 234). On this point, see especially Kennington 1972: 99-100; Bonicalzi 1996 and 1998: 15134; and Dubreucq 2019. 73. AT VII, 441; CSM II, 297. The infancy theory is also connected with Descartes’s theory about the absence in the mind of mnestic species dating back to the gestation period, as discussed with Gassendi. See AT VII, 264; CMS II, 184: “it will hardly convince those who do not see how you are able to think during deep sleep or indeed in the womb. And here I pause 204 simone guidi Later, we read: It is true that, before freeing myself from the preconceived opinions acquired from the senses, I did perceive correctly that two and three make five, and that if equals are taken from equals the remainders are equal, and many things of this kind; and yet I did not think that the soul of man is distinct from his body. But I do not find this surprising. For I can easily see why it happened that, when still an infant, I never made any false judgements about propositions of this sort, which everyone accepts; the reason was that I had no occasion to employ these propositions, since children do not learn to count two and three until they are capable of judging whether they make five. But, by contrast, I had from my earliest years conceived of my mind and body as a unity of some sort (for I had a confused awareness that I was composed of mind and body.74 With respect to the core of the Meditations, what is new of the context of the Sixth Replies is a more overt causal explanation of why we are hindered in perceiving the clear and distinct notion of the mind; from the quite enigmatic ‘spontaneous impulse theory’ to what we may label the ‘infancy theory.’ In essence, Descartes finally makes clear that what we handle when dealing with the ‘thinking matter theory’ is not only a prejudice, but a wrong inference that the mind has had previously, based on embodied experience. Accordingly, infancy, and not the overall compound experience of embodied mind, is now identified as the precise phase of human life during which this wrong mentality is devised.75 It is established by the firm connection that one’s intellect has with imagination and the bodily organs in childhood and is then imposed upon the mind. The processual nature of this lapse of the mind is, in effect, the only manner to explain how this indisputable clearness that we recover in the ‘die-hard mind aragain and ask whether you think that you were infused into the body, or one of its parts, while still in the womb or at birth. But I do not want to press the point too insistently and ask whether you remember what you thought about in the womb or in the first few days or months or even years after you were born; nor, if you answer that you have forgotten, shall I ask why this is so”. Descartes’ reply is as follows: “It is no surprise that we do not remember the thoughts that the soul had when in the womb or in a deep sleep, since there are many other thoughts that we equally do not remember, although we know we had them when grown up, healthy and wide-awake. So long as the mind is joined to the body, then in order for it to remember thoughts which it had in the past, it is necessary for some traces of them to be imprinted on the brain; it is by turning to these, or applying itself to them, that the mind remembers. So, is it really surprising if the brain of an infant, or a man in a deep sleep, is unsuited to receive these traces?” (AT VII, 356-357; CMS II, 254). See Scribano 2015, 54ff. As noted by Scribano, Descartes’s view is further developed in his exchange with the Hyperaspistes (AT III, 400; AT III, 425) and in his 1648 correspondence with Arnauld (AT V, 186; AT V, 192-193). 74. AT VII, 445; CSM II, 300. 75. Indeed, as well noted by Rethy 2000: 661ff., Descartes has a positive view of the “institution of nature”, presented especially in the Passions and somehow contrasted with the “teaching of nature”. Institution of nature consists in the firm connection between “certain physical occurrences in the body with a passion in the soul, which in turn is incited to will a certain state for which the body is prepared, ad which, as in Meditation Six, is later identified as that motion ‘which Is the most proper and generally useful for the preservation of the human body when it is fully healthy’ (AT VII, 87; CSM II, 60, Rethy’s translation from AT IX, 69-70)”. descartes and the ‘thinking matter issue’ 205 gumentM’ is ‘swallowed’ by the unity with the body, without also claiming that the human compound is delusional by its own nature. This lack of evidence is certainly something that occurs to the mind-body composition (during childhood) and is not something that the human composition is in its own nature. The ‘infancy theory’ that he had put forth before the Meditations is now used to save the ‘die-hard mind argumentM’ as a component of the overall ‘prejudice strategy’. Indeed, Descartes anchors a quite traditional distinction between two different and alternative segments of our knowledge to the opposition between infancy and this philosophical adulthood. On the one hand, true science belongs to the mind alone, which is ensured by the clearness and distinctness of the mind that is advocated in Meditation Four. On the other hand, opinion, constructed during childhood by the mingled experience of the mind-body composition, is now entirely broken down and analyzed in the Meditations by means of the methodic doubt and the “clear and distinct” principle. The ‘infancy theory’ allows Descartes to explain how the mind “although it was aware of its own nature and had within itself an idea of thought as well as an idea of extension” (science), became unable to see these evident truths (opinion). CONCLUSION The ‘thinking matter issue’ is not only an important objection raised against Descartes by his opponents, but is also a structural problem of Descartes’s attempt to demonstrate his body-mind dualism. As such, it is negatively present already in the Discourse, where it is entirely neglected. From 1638, it is positively at work in Descartes’ mature version of his metaphysics and notably in Meditations, against Mersenne’s and Pollot’s replies, and in the Replies, once again against Mersenne and Gassendi. Then not only has Descartes considered the ‘thinking matter issue’ to be a major problem for the demonstration of his dualism, but he has also structured the whole Meditation Two in response thereto, including the new role attributed to the cogito argument and to what I called the ‘die-hard mind argument.’ Yet, if this reconstruction is correct, then Descartes’s treatment of the ‘thinking matter issue’ also reveals another important element concerning body-mind dualism in the Meditations. Indeed, it may explain why Descartes points directly to the real and substantial distinction between the two res, thereby rejecting any milder form of distinction.76 Given its premises (a substantial dualism) Descartes’ whole response to the ‘thinking matter issue’ needs to culminate in a real, substantial, and actual distinction between the mind and the body. And this is the vanishing point towards which the ‘prejudice strategy’ points and assumes right from start. In effect, this is the only way to rule out the ‘thinking matter theory,’ denying that the same substance bears two different and contrasting attributes, being at the same time immaterial and material, thought and extension, mind and body. Pace those 76. AT VII, 120-121; CSM II, 85-86. 206 simone guidi interpreters who have endeavored to downplay the strength and the radicality of Descartes’s dualism, this is what he has aimed to do since the Discourse and that which he brings to completion in the Meditations. ACKNOWLEDGMENTS I am sincerely grateful to Miriam Aiello, Lorenzo Giovannetti, Mattia Mantovani, and Antonio Piccolomini d’Aragona for their valuable feedback on an earlier version of this paper. I also extend my thanks to the referees. Any errors that remain are solely my own. ABBREVIATIONS AT = René Descartes, Œuvres, éd. par C. Adam, P. Tannery, J. Beaude et P. Costabel, volumes I-XI, Paris, Vrin & CNRS, 1964-1974. 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