What Descartes Proved

The Latin subtitle of Descartes’ Meditations advertises that they not merely assert but demonstrate the existence of God and an immortal soul. However, as noted in the Cambridge Descartes Lexicon, neither the word “immortality” nor “immortal” even appears in the body of the text. Descartes does convincingly argue that even in the very act of doubting everything, it is apparent that something is going on — that there is awareness or “thinking”, even on the extreme assumption that everything it thinks is mistaken.

“What then did I formerly believe myself to be? Undoubtedly I thought myself to be a man. But what is a man? Shall I say a rational animal? No, for then I should have to inquire what is ‘animal’, what ‘rational’; and thus from one question I should be drawn on into several others yet more difficult. I have not, at present, the leisure for any such subtle inquiries. Instead I prefer to meditate on the thoughts which of themselves spring up in my mind” (Descartes’ Philosophical Writings, trans. Norman Kemp Smith, pp. 203-204).

Descartes argues that bodily phenomena are not clearly “me”, but that I cannot separate myself from my awareness. “Thinking? Here I find what does belong to me: it alone cannot be separated from me. I am, I exist. This is certain. How often? As often as I think” (p. 205).

He makes a subtle transition from arguments about the indubitable existence of some awareness to arguments about something that has the awareness.

“What is a thinking thing? It is a thing that doubts, understands, affirms, denies, wills, abstains from willing, that also can be aware of images and sensations” (p. 206). Elsewhere he also includes love and hate. Using contemporary vocabulary, Gueroult calls this a thinking subject (Gueroult, Descartes, p. 40), a word Descartes himself does not use in this context. Descartes identifies it with his own view of the soul. Though Descartes thinks it is separable from the body and the world, he treats it as a concrete “me”.

This concrete me-thing is supposed to have some very strong properties. Descartes claims it is a substance — apparently in the sense of something underlying — and that we can know something is a substance without knowing it as a substance. Secondly, “Interior to the Cogito, consciousness [French conscience, which predated Cudworth and Locke’s English word] and consciousness of consciousness are identical” (Gueroult, p. 99, my translation, brackets and emphasis added). Thirdly, the Cartesian soul is supposed to have “infinite” free will.

On my reading, the earlier transition from the indubitability of the existence of some concrete awareness — which I take to be genuinely irrefutable — to the assumption of a “thing” that has the awareness, is only valid if the “thing” is strictly identified with the awareness itself. But if the “thing” is identical with the awareness we started with, then the transition to calling it a substance is not justified. Conversely, if “thing” does have strong enough meaning to justify calling it a substance, the transition from thinking to a thinking thing was unjustified.

The identity of consciousness and consciousness of consciousness seems to be a completely unproven and unprovable assumption — one that I think Aristotle, Kant, Hegel, and Ricoeur each convincingly suggest we should oppose. Gueroult quotes Descartes in a letter making the weaker claim that (contrary to what Locke would assert a bit later) the soul is capable of thinking of many things at once. If we accept this, that would make a simultaneity of consciousness and consciousness of consciousness possible in particular cases, but it still falls far short of establishing their identity.

Like many voluntarists, Descartes makes a leap from the much weaker claim that we make real choices, to the ultra-strong claim that our power of choice is completely unconditioned, and that divine omnipotence exempts it from the natural order altogether.

He argues at length that an omnipotent God is the necessary foundation of the razor-thin subjective certainty he discovered by introspection. The arguments about God are introduced as follows: “Those [ideas] which represent substances are without doubt something more, and contain in themselves, so to speak, more objective reality (that is to say participate by representation in a higher degree of being or perfection) than those which represent only modes or accidents; and again, the idea by which I apprehend a supreme God, eternal, infinite, immutable, omniscient, omnipotent, and the creator of all things which are on addition to Himself, has certainly in it more objective reality than those ideas by which finite substances are represented.”

“Now it is manifest by the natural light that there must be at least as much reality in the efficient and total cause. For whence can the effect draw its reality if not from its cause? How could this cause communicate to it this reality if it did not itself have it? And hence it follows… that what is more perfect, i.e. contains more reality, cannot proceed from what is less perfect” (pp. 219-220).

“By the name God I mean a substance that is infinite, immutable, independent, all-knowing, all-powerful, and by which I myself and everything else, if any such things there be, have been created. All those attributes are so great and so eminent, that the more attentively I consider them the less does it seem possible that they can have proceeded from myself alone; and thus, in the light of all that has been said, we have no option save to conclude that God exists” (p. 224).

Out of nowhere, we suddenly have an unexplained appeal to a fully formed late-scholastic distinction between substance, mode, and accident, and other scholastic reasoning about the superiority of causes to their effects. The implicit claim seems to be that these very particular historical formulations are universally given in intellectual intuition.

Descartes’ subsequent argument is literally that God is the efficient and total cause of everything, therefore He exists. Need I point out that only an existing being could be an efficient and total cause in the first place (assuming there is such a thing as a total cause)? And that the argument is therefore patently circular? Though still debatable, Anselm’s ontological proof and the various arguments of Aquinas were much more persuasive than this.

Plotinus, Augustine, and Avicenna all anticipated Descartes’ strong sense of interiority. What was relatively new in the metaphysics of Descartes was his narrow point about the otherwise empty certainty that “awareness exists”, but even that was partially anticipated by Avicenna’s “flying man” argument.

Gueroult on Descartes

Having been greatly impressed by Martial Gueroult’s two extant volumes on Spinoza’s Ethics, I wanted to challenge myself to get some sense of the detail of his magisterial Descartes selon l’order des raisons (1968). Sometimes called a “structuralist” in the history of philosophy, Gueroult systematically developed the fine grain of argument in Spinoza’s demonstrations, and here he does the same for Descartes’ Meditations.

Beginning with a distinction between understanding and explanation, Gueroult announces his intention to subordinate the former to the latter (p. 9). Here “understanding” is a sort of intuitive or imaginative grasp of the whole, whereas “explanation” develops the details in their interrelation. I am reminded of Paul Ricoeur’s great theme of the value of the “long detour”.

Gueroult says Descartes viewed “isolated thoughts” with a sort of horror. This is already interesting. I have long puzzled over Brandom’s treatment of Descartes as a proto-inferentialist, when Descartes has seemed to me on the contrary like an arch-representationalist who plucked “truths” out of thin air. Both Gueroult and Brandom take Descartes’ “method” very seriously. Brandom’s work previously set me on a path that led me to radically change my views of Kant and Hegel. Perhaps I’ll have to revise or modulate some of my judgments of Descartes as well.

For Gueroult, it is objective structures of argument that distinguish philosophy from poetry, spiritual or mystical elevation, general scientific theory, or mere metaphysical opinions. He says that even while “excommunicating” the history of philosophy, Descartes nonetheless formulated a good principle of reading, rejecting eclectic tendencies to pull out this or that idea from a great author, in favor of a systematic approach. Descartes is quoted saying the “precious fruit” must come from “the entire body of the work” (p. 11). This is an important complement to his one-sided insistence elsewhere on beginning with what is simple. However, Descartes is also quoted insisting that all conflicts of interpretation are due to shallow eclecticism and deficiency of method, and that wherever there is such a conflict, one side must certainly be wrong (pp. 13-14).

This insistence on univocal interpretation is one of my big issues with Descartes. It works well for things like geometry, but much less well for sorting out arguments about power or potentiality, for instance. Pushing univocal interpretation as far as it can go can be a very valuable exercise, but as soon as we leave pure mathematics, it also shows its limits. I think that while mathematical necessity can be understood as something we “ought” to recognize for a multitude of reasons, sound ethical judgment must in principle reach beyond what can be expressed with certainty by formal equations. Much as I admire a good mathematical development, I therefore think ethics is more fundamental for us humans than mathematics, and philosophy is more ethical than mathematical.

According to Gueroult, the seminal idea guiding all of Descartes’ work is that human knowledge has unavoidable limits due to the limits of thought, but within those limits it is capable of perfect certainty (p. 15). For Descartes, we do not know thought by things, but we know things by thought. As a matter of principle, we should doubt everything that does not come from the certainty of thought. We are thus offered a stark division between that which is supposed to be certain beyond question, and that which is vain and useless. I think this results both in a treatment of too many things as certain, and in a premature dismissal of aspects of human reality that are uncertain, but nonetheless have real value.

I agree that mathematical reasoning is capable of (hypothetical) certainty, but I contend that we humans live mainly on middle ground that is neither certainty nor mere vanity.

Descartes Revisited

Descartes is among my least favorite of those conventionally termed great philosophers. My treatment to date has been mainly limited to a few dismissive remarks. Here I’d like to add a few “historiographical” points of demarcation.

Insofar as there is general consensus among scholars, Descartes (1598-1650) first and foremost has claim to fame as a very influential promoter of something recognizably close to modern scientific method. He is often credited with the invention of analytic geometry, based on an early recognition of the systematic isomorphism between geometry and algebra. Galileo (1564-1642) had already taken up an approach to natural science based on mathematical analysis, which Descartes enthusiastically adopted. Descartes particularly promoted a methodology based on clear and distinct ideas, which he held to give certain knowledge. He advocated an orderly progression from the simple to the complex.

On a broad social level, Descartes is remembered for promoting the independence of scientific investigation, particularly from the doctrinal concerns of the Catholic Church. But he was also a religious thinker. While confessing in a private letter that he did not literally believe various details of received scripture, he was very engaged with proofs of the existence of God.

Numerous scholars have pointed out that outside the domains of mathematics and natural science, Descartes in many ways remained close to the Latin scholasticism of which he has been commonly regarded as the slayer. In Descartes and the Modern Mind (1952), for example, Albert Balz argued at length that the thought of Thomas Aquinas was an essential precursor to Descartes. I note that Augustine had already emphasized the importance of the interpretive role of reason, even in matters of faith. On Aquinas’ account, God gives us not only revelation, but also the natural light of reason. In Summa Contra Gentiles, Aquinas addressed questions of philosophy and theology entirely from the point of view of that “natural light”, while aiming to show that the natural light of reason independently leads to many of same truths he attributed to revelation. Descartes makes great use of a similar concept of the natural light of reason.

Both Descartes and Aquinas thought the natural light of reason, properly understood, gives us truths, full stop. I think it gives us invaluable criteria for judgment and interpretation, while always in principle leaving room for discussion about what conclusions should be drawn. I also think the “natural light” itself comes to us in degrees, and is never a simple or unproblematic possession.

A different strand of Latin scholastic thought tended to claim that all human knowledge originates in sensible images, while attributing such a view to Aristotle. (I think this is overly strong, and that Aristotle only meant to defend the pragmatic value of sensation against Platonic skepticism about all deliverances of sense.) Descartes famously argued that sensible images are not the only source of knowledge, and I think that is true, as far as it goes.

Here is where Descartes’ theses about clear and distinct ideas come into play. A methodological discipline based on examining whether our ideas are clear and distinct is an important source of human knowledge. Again, this much I can agree with, but I think clarity and distinctness are relative criteria and not absolutes. As relative criteria, they have been implicitly employed by most if not all serious thinkers. I take such evaluations to have been a major implicit concern of Platonic and Aristotelian dialectic, which in part aims to discern meanings that are more clear and distinct.

Descartes effectively claimed that clarity and distinctness are absolute, decidable properties of ideas. One of the broadly scholastic views he sharply criticized was that our best knowledge of sensible things is only “probable”. Descartes claimed that the results of his methodological analyses were certain, in the same way that mathematical conclusions follow with certainty from their premises. This goes well beyond the claim that there is practical value in such methodology.

Building on arguments of Augustine and Avicenna, he also famously gave great importance to the claim that immediate contents of the mind give evidence of unconditional certainty of the abstract existence of something. The very possibility that I could be deceived implies the abstract existence of an abstract something that could be deceived. Further, if something in any way appears to me to be such and such — even if I am wrong about all the details — independent of all the details, the barest fact of the appearance implies that some appearance generically “exists”.

The “I” that is in this way proven to exist and the appearance that is proven to exist are both extreme abstractions. Even Descartes did not claim that either of these existences by itself gives us any further knowledge. From this basis alone, I could still be entirely mistaken about the kind of being that I am, and about every detail of what appears to me to be the case. In spite of the famous Cartesian doubt, Descartes actually wanted to makes strong claims of certainty and to refute skepticism. Many readers have concluded, though, that he opened the door for a new, more global form of skepticism, because what he clearly establishes as certain seems so utterly lacking in content.

I would hasten to add that unreasonable, excessive skepticism about human knowledge is best refuted by successful achievements of goals in real-life situations. Only a hypocrite could claim to live in the world with no well-founded beliefs whatsoever. The ancient Skeptics were only “skeptical” about theoretical accounts of things, not about practical concerns of everyday life.

By setting the bar too high and aiming at absolute certainty, Descartes actually opened the door for more radically subjectivist views that no one in the ancient world would have taken seriously (and not just because ancient people were naive). At the same time, he was very impatient with “dialectic”, and tended to foreshorten discussions of meaning and interpretation, in favor of claims that certain contents are unequivocally clear and distinct. Thus the ultimate result of his thought oscillates unstably between extremes of “Cartesian” skepticism and dogmatism.

Another point on which Descartes has been very influential is his strong representationalism. For Descartes, strictly speaking we never have practical knowledge of things in the world, only knowledge about contents of our mental representations, insofar as they are clear and distinct. In particular, we only know bodies through our mental representations of them. Rather than consisting in an interpretive stance of a situated being in the world, the Cartesian cogito achieves its purely subjective certainty in a way that is supposed to be peculiarly “outside” the real world altogether.

Unlike the representationalism of Locke, which is grounded in a kind of empirical psychology, that of Descartes is closely bound up with an ontological mind/world dualism more radical than anything Plotinus, Augustine, or Avicenna ever contemplated. For Plotinus, Augustine, and Avicenna, the soul was a very special kind of “something” existing in the real world, even if for Plotinus and Augustine it was not a “subject” in the sense of something underlying something else. For Locke — the other great early modern promoter of representationalism — our mental worlds are ultimately contained within the natural world. For Descartes, there is the world and there is the soul, and never the twain shall meet. The soul has its own mental world where it seems to relate directly only to God, and human knowledge occurs only in that mental world.

It is due to this unprecedentedly radical mind/world dualism of Descartes, I think, that virtually no one — even among his admirers — wants to uphold his metaphysics. This is an extreme example of what Hegel called “alienation”.

Circling Toward Absoluteness

Hegel prominently refers to “absolute” knowledge as a kind of circle. Here I think he has in mind Aristotle’s notion of the “perfection” of circular motion. This in turn presupposes a Greek notion of “perfection” that — unlike the more theological sense it acquired later — is intended to be something realizable or finitely achievable, a kind of completeness within itself of a finite essence with respect to its ends that is still compatible with life and motion, and indeed requires the latter. The perfection of absolute knowledge also has to be construed in a way that is modest enough to allow for the contingency that comes with inhabiting a world. It is actually much more ethical than epistemological.

The circle metaphor here also involves an aspect of returning to the beginning. The immediate subjective “certainty” that throughout Hegel’s long development has been distinguished from real essential “truth” finally becomes adequate to the expression of “truth”, in part by going through development and learning from its mistakes, and in part by letting go of its self-centered pretensions.

The specific kind of completeness within itself involved here has to do with the way knowing, doing, and forgiving are brought together. Harris in his commentary says that for Hegel the putting together of knowing and doing — when its implications are followed out — leads “logically” to what Hegel has been calling the breaking of the hard heart, which Hegel also identifies with the forgiveness stressed in historic religious traditions.

“‘Immediate Dasein‘ [concrete, implicitly human being] already has no other significance than that of ‘pure knowing’ for the active Conscience. My conscientious conviction is that I have done the best I can in the circumstances as they are known to me; my ‘pure knowledge’ is precisely that it is my duty to do that. We expect, in simple justice, to be forgiven for the errors caused by ignorance; the [Sophoclean tragedy] Oedipus at Colonus already makes this point quite clearly. Of course, in my uneasy ‘shifting’, I do learn how ‘impure’ my motives always are. But the forgiving community comprehends and forgives the fact that I saw the whole situation in my way, and defined my duty according to some personal interest that is not universally (or as Kant would say ‘categorically’) imperative. Thus the community reduces ‘actuality’ to the pure knowledge of what the inevitable conditions of acting are.”

“The ‘determinate Dasein‘ that arises from action and judgment in their ‘relationship’ is the forgiving that comprehends the action in its concreteness. The acceptance of the action as ‘conscientious’ — or as objectively rational — involves as its ‘third moment’ the Spirit that says ‘Yes’ (rather than ‘No’, as the moral spirit must say). When the two sides are thus reconciled, the ‘universality’ or ‘essence’ in which both are comprehended is the ‘I = I’ or ‘the Self’s pure knowing of itself’.”

“This ‘pure knowing’, as a concrete experience, is necessarily both an achievement (for the two sides do indeed clasp hands in reconciliation) and an end or goal to be achieved (for we may spend a lifetime trying to comprehend the objective rationality of the other’s act or judgment)…. [I]n principle, this is how the singular rational self — the recognized Conscience or justified sinner, simul peccator et justus [simultaneously sinner and justified] in Luther’s phrase — both constitutes the community, and is constituted by it” (Hegel’s Ladder II, pp. 720-721).

“If consciousness is to come to the comprehension of what ‘truth’ is, (or what the word signifies) through a process of self-criticism that we [readers of the Phenomenology] simply observe, then we must necessarily begin from the side of the ‘for-itself’. The communal substance of our rationality is the ‘in-itself’ which can only gradually come to be ‘for itself’; and its last step must be later….”

“It is, of course, the motion of ‘the Concept’ as self-critical that drives both sides onward; but it is a mistake to identify the motion of the Concept with philosophy as speculation (or even as both speculation and critique) because the concrete historical movement of the whole world… is so essential to it. The lesson that philosophy is not to be understood apart from its history is widely understood; what Hegel’s science of experience teaches us is the much more demanding imperative that philosophy and religion must be comprehended together in the context of the actual history of the human community” (p. 722).

“The Concept” is Hegel’s term for concrete human thought for which there is none of the separateness that the object always has for what he calls Consciousness. This realizes Aristotle’s suggestion that in the case of pure thought, we ought not to separate the act of thinking or the thinker from the thing thought.

In the corresponding part of his separate quick overview Hegel: Phenomenology and System, Harris says, “The Self of Cognition has been shown to be the mediating moment between the finite spirit and the absolute Spirit. It is the self of the infinite community — the incarnate Logos, the ‘I that is We’. Now we have to show (on the one hand) how this absolute Concept comprehends all the experiences that have led us to it and (on the other hand) how we, as singular consciousness, actually comprehend it. We all embody the Concept (before we do any philosophizing at all) because it comprehends us — that is, it provides the context of all that we intelligently say and do, and of everything that we understand about what is unintelligent.” (p. 92).

“The human self is Yorick [the skull contemplated by Hamlet, as Hegel recalls]; our singularity is identical with our ‘thinghood’…. Finally, the sensible thing has to be understood as the essence of the self. This happened for us in the stabilization of the moral self as Conscience” (p. 93).

Conscience already identifies (its own point of view on) what it actually does as a direct expression of its essence. But what Conscience actually did and its consequences also have the same kind of retrospective, socially available “objective” status as Yorick’s skull.

Finally “It is the perfection of Conscience in Forgiveness that gives rise to the singular self as the pure knowing of the community” (ibid).

Aristotelian Probability

Things Aristotle calls “probable” have nothing to with statistics. The legal notion of “probable” cause is much closer to Aristotle’s concept of probability. It refers to conclusions for which there are good reasons, but which are not expected to be established beyond reasonable doubt.

Mathematics achieves certainty and rigorous necessity through the artifice of abstracting away real-world complication and ambiguity. Whenever we are concerned with the real world as we actually experience it, whatever conclusions we reach at best follow probably rather than necessarily.

Keeping in mind the probable character of judgment in general should not prevent us from acting decisively. This kind of “probability” is all the basis we need to have well-founded practical confidence. We can have strong confidence without false pretenses of certainty.

To claim certain knowledge in these cases amounts to what Kant called dogmatism. The deep roots of American pragmatist philosophy have more to do with something like an Aristotelian emphasis on the practical sufficiency of probable judgments than with later reductive, utilitarian theories of value. (See also Aristotelian Dialectic; Dialectic Bootstraps Itself; The Epistemic Modesty of Plato and Aristotle; Demonstrative “Science”?; Kantian Discipline; Copernican.)

Aristotelian Demonstration

Demonstration is literally a showing. For Aristotle, its main purpose is associated with learning and teaching, rather than proof. Its real objective is not Stoic or Cartesian certainty “that” something is true, but the clearest possible understanding of the substantive basis for definite conclusions, based on a grasping of reasons.

Aristotle’s main text dealing with demonstration, the Posterior Analytics, is not about epistemology or foundations of knowledge, although it touches on these topics. Rather, it is about the pragmatics of improving our informal semantic understanding by formal means.

For Aristotle, demonstration uses the same logical forms as dialectic, but unlike dialectic — which does not make assumptions ahead of time whether the hypotheses or opinions it examines are true, but focuses on explicating their inferential meaning — demonstration is about showing reasons and reasoning behind definite conclusions. Dialectic is a kind of conditional forward-looking interpretation based on consequences, while demonstration is a kind of backward-looking interpretation based on premises. Because demonstration’s practical purpose has to do with exhibiting the basis for definite conclusions, it necessarily seeks sound premises, or treats its premises as sound, whereas dialectic is indifferent to the soundness of the premises it analyzes in terms of their consequences.

We are said to know something in Aristotle’s stronger sense when we can clearly explain why it is the case, so demonstration is connected with knowledge. This connection has historically led to much misunderstanding. In the Arabic and Latin commentary traditions, demonstration was interpreted as proof. The Posterior Analytics was redeployed as an epistemological model for “science” based on formal deduction, understood as the paradigm for knowledge, while the role of dialectic and practical judgment in Aristotle was greatly downplayed. (See also Demonstrative “Science”?; Searching for a Middle Term; Plato and Aristotle Were Inferentialists; The Epistemic Modesty of Plato and Aristotle; Belief; Foundations?; Brandom on Truth.)

Foundations?

Foundationalism is the mistaken notion that some certain knowledge comes to us ready-made, and does not depend on anything else. One common sort involves what Wilfrid Sellars called the Myth of the Given.

Certainty comes from proof. A mathematical construction is certain. Nothing in philosophy or ordinary life is like that. There are many things we have no good reason to doubt, but without proof, that still does not make them certain.

In life, high confidence is all we need. Extreme skepticism is refuted by experience. It is not possible to live a life without practical confidence in many things.

Truth, however, is a result, not a starting point. It must be earned. There are no self-certifying truths, and truth cannot be an unexplained explainer.

In philosophy, we have dialectical criticism or analysis that can be applied from any starting point, then iteratively improved, and a certain nonpropositional faith in reason to get us going. All we need is the ability to question, an awareness of what we do not know, and a little faith. We can always move forward. It is the ability to move forward that is key. (See also Interpretation; Brandom on Truth; The Autonomy of Reason.)

Inferentialism vs Mentalism

Brandom’s “inferentialism” or emphasis on material inference effectively makes what I call ethical reason the most important thing in the constitution of subjectivity — not psychology, and not some putative immediate mental presence, or universal transparent representational medium, or supposedly perfect reflexivity.

This is not to deny that there is such a thing as immediacy; it is rather to specify that immediacy is not foundational, and has nothing to do with certainty. Immediacy has a very different role to play, in showing us the world’s “stubborn recalcitrance to mastery and agency” and providing occasions for learning. (See also Mind Without Mentalism; Psyche, Subjectivity.)