Descartes and the notion of animal spirits: a brief historico-philosophical remark on Sonya Marie Scott's 'Crises, confidence, and animal spirits: exploring subjectivity in the dualism of Descartes and Keynes'

Abstract

In 'Crises, confidence, and animals spirits: exploring subjectivity in the dualism of Descartes and Keynes,' Sonya Marie Scott sets out to deepen our understanding of Keynes' use of animal spirits in his influential work in economics, by exploring one of the sources from which he appears to have acquired the notion- in the work of Seventeenth-Century philosopher René Descartes. The examination to follow will focus almost exclusively on Descartes's view, where I hope to bring to light, for future discussion, both historical and philosophical troubles lurking in the account of Descartes as found in Scott's article. I shall focus on two issues: first, I shall say a few critical words about the analogy offered by Scott, the analogy between Descartes's and Keynes' respective 'dualisms;' secondly, I shall look briefly at Scott's reading of Descartes on animal spirits. As a quick bit of preliminary stage-setting, let me preface my remarks with a brief account of Descartes's dualism and his account of the human being.

Headnote

Abstract: In 'Crises, confidence, and animals spirits: exploring subjectivity in the dualism of Descartes and Keynes,' Sonya Marie Scott sets out to deepen our understanding of Keynes' use of animal spirits in his influential work in economics, by exploring one of the sources from which he appears to have acquired the notion- in the work of Seventeenth-Century philosopher René Descartes. The examination to follow will focus almost exclusively on Descartes's view, where I hope to bring to light, for future discussion, both historical and philosophical troubles lurking in the account of Descartes as found in Scott's article. I shall focus on two issues: first, I shall say a few critical words about the analogy offered by Scott, the analogy between Descartes's and Keynes' respective 'dualisms;' secondly, I shall look briefly at Scott's reading of Descartes on animal spirits. As a quick bit of preliminary stage-setting, let me preface my remarks with a brief account of Descartes's dualism and his account of the human being.

Keywords: mind, rationality, economics

Preliminaries

Descartes establishes his dualism by first showing that mind and body are really distinct, which establishes the claim that mind and body can exist independently of one another. He suggests that two substances are really distinct if, and only if, we can conceive the nature of the one independently of the nature of the other, and vice versa. He famously argues for this in the Sixth Meditation (AT VII 78; CSM II 54), [1] but scholars agree that the notion of real distinction is more clearly articulated in the Principles (AT VIIIA 28-9; CSM I 213). Cartesian dualism is the metaphysical view that exactly two kinds of finite substance constitute the inventory of 'things' found in the created cosmos: mind, whose defining attribute is to think; and body, whose defining attribute is to be extended in three dimensions- in length, breadth, and depth. In the Synopsis of the Meditations (AT VII 13; CSM II 10), Descartes goes as far as to say that the two kinds of finite substance are not only different (diversæ ) but are opposites (contraria), where mind, a thinking thing, is (essentially) not extended and body, an extended thing, (essentially) does not think. Once real distinction is established, he goes on in the Sixth Meditation to show that not only can they exist independently of one another but do exist independently of one another. (AT VII 80; CSM II 55)

We also find in the Sixth Meditation Descartes's account of the human being, which he says is a union of the two really distinct kinds of finite substance, mind and body. But even the earliest readers of Descartes's work raised a 'problem' for his view- the problem of the notion of the union. One of the first to raise the concern was Princess Elisabeth of Bohemia (in a 6 May 1643 letter: AT III 660), who had corresponded with Descartes at length about his philosophical views. Elisabeth had argued that if causation was to be understood in terms of contact, a conceptual problem emerges. We might think, for instance, that one body causes something to occur in another body by way of contact, where contact is understood to occur via their respective surfaces. Thus, body-body causation seemed perfectly intelligible. But since minds are not extended, they cannot have shapes. And, in lacking shapes they cannot have surfaces. Thus, contact is rendered impossible (or meaningless) when it comes to talking about minds. There simply would be no way to conceive how mind and body could causally interact, which, as Elisabeth suggests, would call into question the very possibility of mind-body union- which is tantamount to calling into question the very possibility of the human being.

Descartes took Elisabeth's critique seriously and addresses it in what would turn out to be his last work: the Passions of the Soul. Yet, even prior to the Passions, as noted above, Descartes had cast the human being as a union of mind and body. The views offered in the Sixth Meditation and in the Passions are essentially the same. In any case, the view isn't the one famously depicted by Byle. Byle says that for Descartes the mind inhabits a body like a ghost in a machine. Scott relies heavily on Byle's reading of Descartes, which, in my view, unnecessarily embroils Scott in serious troubles.

Consider what Descartes says in the Sixth Meditation:

Nature also teaches me, by these sensations of pain, hunger, thirst and so on, that I am not merely present in my body as a sailor is present in a ship, but that I am very closely joined and, as it were, intermingled with it, so that I and the body form a unit. If this were not so, I, who am nothing but a thinking thing, would not feel pain when the body was hurt but would perceive the damage purely by the intellect, just as a sailor perceives by sight if anything in his ship is broken. (AT VII 81; CSM II 56)

If we take this sort of passage seriously, Descartes is denying that the mind sits watch over the body, as a sailor does with his ship, and instead casts the mind and body as being 'intermingled' in such a way that the human being feels the damage done. The human being doesn't simply think pain, it feels it. The human being is unique- it isn't simply a pairing of a previously 'disembodied' mind with a body. In a letter to his friend Regius, Descartes writes: 'If an angel were in a human body, he would not have sensations as we do, but would simply perceive the motions which are caused by external objects, and in this way would differ from a real man.' (AT III 493; CSMK III 206) So, the 'embodied' mind of a human being is not like the 'embodied' mind of an angel. The mind of the angel, it seems, would sit watch over the body, perceiving any damage to the body, as a sailor might perceive damage to his ship- but this would not be the case for the mind of a human being.

Not surprisingly, there have emerged interesting discussions in the secondary literature over the issue of the union. For instance, some have entertained the possibility that the union- that is, the human being- is a third substance that arises from the two more fundamental substances, mind and body. 121 Such scholars, however, have had to contend with the following sort of counter- argument: given that mind and body are really distinct substances, demonstrated by the fact that we can conceive the nature of each independently of the other, where the implication is that really distinct substances can exist independently of one another, it will follow that the human being is not itself a substance. For, insofar as the human being is the union of mind and body, human beings cannot exist independently of mind and body. No mind and body, no human being. Even so, whatever the ontological status of the union was for Descartes, scholars seem to be in full agreement that the Cartesian human being is not simply a thing (a mind) 'housed' in another thing (a body), like a sailor in his ship. Ryle's reading of Descartes, then, arguably reveals more about Ryle than Descartes.

Troubles with the analogy

Scott draws an analogy between Descartes's metaphysical dualism and what she refers to as Keynes' economic dualism. Early in the paper, the analogy appears to apply as follows: mind is to body as economic rationality is to the economic body. This analogy strongly suggests, of course, that the economy, the system, is analogue to the human being. That is, the union of economic rationality and the economic body is to the economy as the union of mind and body is to the human being. This way of understanding the analogy is strengthened when Scott emphasizes what she sees to be the opposing traits of mind and body, namely, mind's being essentially rational and body's being essentially non-rational. Talk of the influence of the rational and non-rational with respect to the production of human action, Scott claims, is an important component of Descartes's explanation of the human being. Analogously, Scott suggests that Keynes is claiming that the economy, which for the moment I am taking to be analogous to the human being, is constituted of two distinct or opposing forces, so to speak, where one was essentially rational and the other essentially not. Talk of the influence of the rational and non-rational with respect to the production of economic activity, Scott claims, will be an equally important component of Keynes' explanation of the economy.

But there is trouble lurking. For instance, when introducing the notion of what Scott refers to as the economic body, Scott identifies it as the economy itself, where she goes on to say (e.g. in footnote 2) that by 'economy' she means nothing other than what is commonly understood by the term. If so, the economy will be taken to be a system or network of consumers, producers, and distributors of goods and services. Consequently, the economic body will be this entire economic system. If this is so, the analogy, as previously cast, falls apart. For, as previously cast, Keynes' economic body was analogue to Descartes's body and Keynes' economy, the system, was analogue to Descartes's human being. But, if the economic body is the system itself, Keynes' economic body will not be analogue to Descartes's body, but will instead be analogue to Descartes's human being. Thus, the analogy cannot be: economic rationality is to the economic body as mind is to body. Instead, the analogy must be: economic rationality is to the economy as mind is to the human being.

As stated in the Preliminary section, mind and body, the two really distinct finite substances, constitute Descartes's dualism. But mind and the human being do not, for the mind and the human being are not really distinct substances. For Keynes to lay claim to his economic dualism, based on Descartes's metaphysical dualism, economic body cannot be identical to the economy- that is, it cannot be identical to the system. So, Scott may have to say more to clear this up.

Further troubles lurk. Begin by again emphasizing that for Descartes not only can mind exist independently of body but can exist independently of the human being. This also holds for body, namely, that not only can body exist independently of mind, it, too, can exist independently of the human being. The human being, however, cannot exist independently of the mind or the body. For Keynes to align his economic dualism with Descartes's metaphysical dualism, even if only by analogy, it would have to be that not only can economic rationality exist independently of the economic body (whatever that may be), but can exist independently of the economy, the economic system itself. Likewise, not only can the economic body (again, whatever that may be) exist independently of economic rationality, but can exist independently of the economy, of the system itself.

Now, will Keynes hold that economic rationality can exist independently of an economy? Moreover, can the economic body exist independently of an economy? Or, are their relationships really the reverse of Descartes's? That is, on Descartes's view the human being arises from the 'intermingling' of the mind and body, from the union of two really distinct substances, two substances that can, and in Descartes's ontology, do exist independently of one another. And, perhaps more to the point, the two can exist independently of the human being. Can the same be said for Keynes' view? Will it even make sense, for instance, to talk of economic rationality as something to be encountered independently or outside of an economic system? Can economic rationality and economic body be found doing their thing, whatever that would be, independently of one another and independently of any economy or economic system? Or, should we instead read Keynes as holding that the economy, the system, is the 'thing,' the phenomenon to be explained, and that economic rationality and economic body make their appearance as the result of conceptual analysis, where neither can really exist independently of the system or of one another? If so, the relationships between the economy and economic rationality and economic body are closer, in terms of metaphysical analogies, to an Aristotelian hylomorphism, where the 'thing,' such as a human being, is the hylomorphic unity, and that which constitutes this unity is form and matter. On this proposal, the union of economic rationality and economic body is to the economy as the unity of form and matter is to the human being.

Animal spirits, the non-rational, and God

Scott argues that for Descartes the animal spirits play 'a central role in the mediation between mind and body,' where they mediate 'between the rational and non-rational, by their effect on the pineal gland.' For Keynes, they represent non-rational impulses which 'come up against a certain form of economic rationality.' They apparently represent what Scott calls 'the optimistic (non-rational) self.' Leaving aside the problematic notion of a non-rational self (Descartes would not ever identify body as constituting any aspect of the self, of the T that thinks), it is never made clear why anyone would think that the non-rational influences on human decision-making or on human action would necessarily be 'optimistic.' But troubles are worsened, I think, when Scott suggests that in serving as mediators the animal spirits have a kind of 'material existence' and are like bodies. I want to now address these claims.

As Scott rightly points out, Descartes took the animal spirits to function as communicators of motion, and with respect to the human body, as communicators of motions to and from the interior cavity of the brain, in which the pineal gland was located. Suppose that one is pricked with a pin. The story, or at least part of it, of how one feels the prick goes as follows: the pin introduces motion into the tiny particles that constitute the skin. This motion is communicated to the nerves, which are tiny tubules filled with a mist constituted of very fine particles- the animal spirits. The motion is quickly communicated by way of this system of fine particles through the nerves and into the interior cavity of the brain. There, the animal spirits might communicate this motion to the pineal gland, perhaps moving it ever so slightly in one direction or another. This movement, instituted by God, would occasion, say, an idea of pain. Of course, this pain isn't simply thought, but, as Descartes says, is felt, and in particular, is felt at the location of the prick. The phenomenology here is difficult at best, for Descartes says very little about the phenomenological difference between having an idea of pain and feeling pain. So, the account of union is still murky. But the role of the animal spirits is clear enough- they serve as communicators of motion.

Now, as Scott also notes, the notion of animal spirits had been around long before Descartes. They were typically understood, as I say above, to be fine particles, a large collection of such particles appearing like a gas or a mist to the naked eye- if they were visible at all. The vapor emitted by ammonia, for instance, might serve as an example of animal spirits. If one were to take a whiff, one's head would immediately snap back. The idea here is that the particles constituting this vapor are so small that they moved through the porous parts of the skull and entered directly into the interior cavity of the brain, where they moved the pineal gland, producing in the one smelling the ammonia the snapping back of the head. But gases and mists and the like are, on Descartes's view, systems of very small particles whirling about. Scott says that they are like bodies. But on Descartes's view they are not like bodies, they are bodies! They are in essence no different from the pin, the skin particles, the nerve-tubules, the brain, or the pineal gland (or from even the 'empty space' that separates these things). The only difference is a modal one- each particle is very small and moves very fast.

It is not clear why Scott casts the animal spirits as 'mediators' between mind and body. Doing so, especially if the animals spirits are understood to be corporeal, completely ignores the mind-body problem, originally raised by Princess Elisabeth. If the animal spirits are bodies, even though very small, that will not explain how they interact with mind. For, as was noted in the Preliminary section, minds do not have surfaces since they do not have shapes, and they do not have shapes since they are not extended. How will the mind come into contact with a body, regardless of size, or how will a body come into contact with the mind, if the mind has no surface with which to come into contact? How is interaction possible? The introduction of the animal spirits will not solve this problem, and there is no evidence to suggest that Descartes thought that his having introduced them solved it. His view was that although our sensory experience constantly demonstrates to us that mind and body do interact, there was ultimately no way for us to understand or to conceive how they do. It was a union instituted by God, and that was about as good an account as could be given.

Lastly, I should say something about Scott's use of 'non-rational,' when speaking about the influence of the animal spirits on human decision-making or on human action. In Part Two of the Principles, Descartes says that the necessity of the laws of nature is grounded in the immutability of God's will. (AT VIII 62; CSM I 240) Scholars also note that for Descartes there is no real distinction between God's intellect and God's will; they are one and the same. Creating the cosmos is an act of God's will, though, as just stated, it might equally be taken to be an act of God's intellect. If God thinks something, God wills it, and vice versa. And, if God wills it, God creates it, and vice versa. In the Sixth Meditation, Descartes says:

For if nature is considered in its general aspect, then I understand by the term nothing other than God himself, or the ordered system of created things established by God. (AT VII 80; CSM II 56)

The point here is that the order of the material world, in being part of nature, is instituted by God. It is of divine origin. God wills the order, which is only conceptually distinct (and not really distinct) from God's thinking it. And, on Descartes's view, no being is more rational than God. So, Scott will need to make clearer Keynes' take on the non-rational, if by that he means the influence of body on the 'embodied' (human) mind. For, although the particular human mind may not understand the import or reason for the 'impulse' produced by the body (or the animal spirits), God certainly understands it. Thus, Keynes' dualism of rationality and non-rationality, though aligned with a very narrow cross-section of Descartes's view, is not aligned with Descartes's 'big picture.' For, ultimately, nothing in the cosmos can be non-rational, despite the fact that much of the cosmos may be utterly unknowable to the finite intellect. In light of this, it would be interesting to learn more from Scott about the import of the non-rational in Keynes' view. Could we, for example, substitute non-rational in Keynes' view for that which is not dependent on the mind of an individual actor? How might that alter Scott's reading of Keynes? I look forward to Scott's replies.

Sidebar

Kurt Smith is Professor in the Department of Philosophy, Bloomsburg University of Pennsylvania (USA) ([email protected]).

Footnote

Endnotes

[1] Henceforth, when citing Descartes, I shall cite the 11-volume collection, Oeuvres de Descartes, edited by Charles Adam and Paul Tannery (Paris: Vrin, 1976). I shall refer to this as 'AT,' followed by the volume and page numbers. Whenever possible, I shall use the English translation of Descartes's work, in The Philosophical Writings of Descartes, 3 volumes, translated by John Cottingham, Robert Stoothoff, and Dugald Murdoch (Cambridge: Cambridge University Press, 1988). I shall refer to this as 'CSM' (or to volume 3 as 'CSMK,' where Anthony Kenny has been added as an editor), followed by the volume and page numbers. AT and CSM citations will be put side by side, separated by a semicolon.

[2] See, for example, Paul Hoffman's 'The Unity of Descartes's Man,' The Philosophical Review, 93:3 (July 1986), 339-70.