Flying Man?

Back in 2019, I included the following in a tangent near the end of a longer post:

“The thrust of the famous cogito ergo sum was already anticipated in Augustine’s Confessions. A more detailed version was developed by Avicenna, in an argument known… as the “flying man”. He proposed a thought experiment, considering someone in counterfactual absolute sensory deprivation from birth, with the intent of asking whether awareness could be completely independent of sensibility. He argued that the person in absolute sensory deprivation would still be aware of her own existence, due to a pure immediate reflexive awareness intrinsic to the soul and independent of the body. This kind of claim would have been accepted by Plotinus, but rejected by Aristotle or Hegel. Medieval Augustinians, however, enthusiastically adopted many of Avicenna’s ideas.” Peter Adamson, a scholar of Islamic philosophy, has a nice short article on this.

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).

Descartes’ 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 better.

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.

Cartesian Metaphysics

For Descartes, according to Gueroult, “metaphysics” is the universal science or the system of science, and also a kind of introduction to more concrete studies. Here we are far from Aristotle and much closer, I think, to Duns Scotus. Without knowledge of God and oneself, Descartes says, it would never be possible to discover the principles of physics. Gueroult says that Descartes insists on an “incomprehensibility” of God that is neither unknowability nor irrationality but the “formal reason of the infinite” (Descartes selon l’order des raisons, p. 17). This again has a somewhat Scotist sound to my ear.

The infinitude of God puts God absolutely first, as the first truth that founds all others. Gueroult quotes Descartes saying, “It is a ‘blasphemy’ to say that the truth of something precedes God’s knowledge of it…, because the existence of God is the first and the most eternal of all the truths that can be, and the truth from which all the others proceed” (ibid; my translation).

Descartes says that God “freely creates” eternal truths. I have no idea what creation of eternal truths could even possibly mean, though such a notion seems to be at least implicit in the teaching of Duns Scotus. To be eternal is to have no before and after. Therefore, it seems to me, all eternal things must be co-eternal. This point of view accommodates part of Descartes’ thesis, insofar as if all eternal things are co-eternal, then an eternal truth would not “precede” God’s knowledge of it. In broadly neoplatonic terms, eternal truths could plausibly be regarded as aspects of the “nature” of God. I can also grasp the idea of truths following logically from the “nature” of God, but I suspect Descartes would either follow Scotus in arguing that God’s infinite power is not a “nature”, or follow Aquinas in arguing that God is pure existence and has no other “nature”. I don’t see how anything more specific can directly follow from either infinite power or pure existence.

For Descartes, though, God’s omnipotence “excludes the possibility of error” and “alone founds the objective validity of my intellectual faculty” (ibid). Descartes aims at “a total system of certain knowledge, at the same time metaphysical and scientific, … entirely immanent to mathematical certitude enveloped in the clear and distinct intellect, … in its requirement of absolute rigor. This totality of the system is in no way that of an encyclopedia of material knowledge effectively acquired, but the fundamental unity of the first principles from which follow all possible certain knowledge” (p. 18). Descartes’ doctrine is for him “a single block of certainty” (p. 19) that would be falsified by adding or removing any detail. All this seems way too strong to me.

Gueroult points out that Descartes wants to contrast an “order of reasons” with an “order of material”, as being more principled. However, unlike geometry, the total system of metaphysical reasoning for Descartes has “psychological” as well as logical requirements. Gueroult says it is for this reason that the Meditations best represent Descartes’ paradigm of rigorous analytic demonstration.

Granted that there is a clear “psychological” aspect to the Meditations, at this point I’m unsure what it means to relate that to the claimed rigor of the system. Moreover, adding a “psychological” dimension to what was said before about mathematical reasoning affects the very meaning of the claim of rigor. I think I understand what mathematical rigor is. I do not understand what “psychological” rigor would be in this context, but I suspect it may be wrapped up with what I would call extraordinary presumptions of absolute self-transparency and immediate reflexivity.

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”.

“Western Metaphysics”?

“Metaphysics” has historically had numerous senses, mostly rather far from the way I read the original Aristotelian context. Neoplatonic commentators and later giants like Avicenna, Aquinas, and Scotus already radically reconfigured its meaning, long before the changes associated with early modernity. Authors like Heidegger and Derrida have famously made sweeping indictments of the whole of “Western metaphysics”, based on overly homogeneous and continuist interpretations of the history of philosophy. More broadly, Plato and Aristotle are far too often blamed for views they never held. Even the medieval Latin tradition was far more diverse and interesting than common stereotypes would allow.

Receptive Power?

The later neoplatonists developed a subtle and somewhat paradoxical notion of passive or receptive power. I call it paradoxical because “passive power” almost seems like an oxymoron. In modern terms, it is hard to see how something purely passive could meaningfully contribute to an effect, or even be called a “power”. But in a neoplatonic context, active and passive powers function as correlative terms that collaborate — albeit asymmetrically — to produce effects. When a “patient” is properly prepared, an appropriate “agent” power is supposed to spontaneously come to dwell within it.

All the change is on the side of the patient, whereas what is called “agency” in neoplatonism belongs on the side of the eternal and unchanging. Exactly how a patient in time comes to be properly prepared to be receptive to an eternal agent when it was not before is admittedly rather obscure.

In his late polemics against Pelagius, Augustine treated the agency of grace as residing entirely on the side of the eternal, even going to the extreme of denying that grace in any way depends on the merit or innocence of the recipient. His point seems to have been that grace does not depend on any kind of self-will, no matter how virtuous or innocent it may be — that it is always only received as a gift.

However obscure the neoplatonic notion of the preparation of patients may seem, in the context of a problematic like that of late Augustine, the attribution of effective reality to passive powers suggests a way out of the impasse we are left with if we consider only grace and self-will. Merit or innocence could be considered as configurations of such “passive powers”.

Proclus’ Elements

The later neoplatonist Proclus (412-485 CE) was head of the Platonic Academy in Athens, at a time when the Athenian Academy was somewhat notorious as the intellectual center of resistance to the spread of Christianity in the Roman Empire. Nonetheless, his work had a profound influence on the Arabic, Byzantine, and Latin traditions. He is usually cited as the main philosophical influence on the early Christian theologian pseudo-Dionysius, who was taken very seriously by Albert the Great and Thomas Aquinas.

Proclus wrote extensive commentaries on Plato, as well as an influential commentary on book 1 of Euclid’s Elements of Geometry. Hegel called him the greatest dialectician of antiquity. Though I think Hegel by his own principles really should have given that title to Aristotle, Hegel was right to recognize Proclus as important.

Aquinas is credited with recognizing that the Latin Book of Causes — a translation of the Arabic Discourse on the Pure Good — was mostly derived from Proclus’ Elements of Theology. Aquinas treated Proclus himself with considerable respect. Dietrich of Freiberg made significant use of his work, and his student Berthold of Moosburg wrote a very long commentary interpreting the Elements of Theology in Christian terms. The Renaissance theologian Nicolas of Cusa and the maverick Giordano Bruno were much inspired by Proclus.

Along with Spinoza’s Ethics, Proclus’ Elements shares the peculiar distinction of being written in a style visibly influenced by Euclid’s Elements. Euclid’s work has often been cited as a sort of paradigm of demonstrative reasoning. Though Proclus, unlike Spinoza, did not work from explicit definitions and postulates and used a looser style of demonstration, his Elements consists of theorems and a sort of demonstrations.

Proclus defends the neoplatonic idea of a One that transcends being, but as Gwenaëlle Aubry and Laurent Lavaud point out in the introduction to the French collection Relire les Éléments de théologie de Proclus (2021), perhaps his most influential idea is that of a very strong continuity from the highest principles to the most mundane effects, which has been read as a strong assertion of immanence as well as transcendence. He is an important source for all the later theological traditions that want to argue for simultaneous immanence and transcendence.

Proclus very explicitly crystallizes what I have called the generalized “unmoved mover” model of causality in Plotinus. For Proclus, “higher” and “lower” causes cooperate in the constitution of worldly things, but the higher cause is always more of a cause than the lower cause. At the same time, he rejects Plotinus’ identification of matter with evil, while emphasizing all of Plotinus’ more positive affirmations of the goodness of manifestation and the beauty of the cosmos.

In a separate treatise On Providence, he develops a sort of epistemic analogue to the generalized unmoved mover theory. “Providence” (pronoia — literally, “forethought”) is a knowledge-like thing that is superior to knowledge in that it is supposed to be eternal and unextended, and to involve no separation of what we might call subject and object. Proclus develops a subtle and suggestive account of something metaphorically like implicit, unextended “seeds” of forms within the overflowing of the One that transcends all extended form. While the One does not “know” worldly things, it “pre-knows” their unextended “seeds”, within something like what Schelling later paradoxically called the identity of identity and nonidentity.

In the Elements, Proclus argues for an interdependence of being, life, and intellect. While one obvious reading of this would emphasize a foundational role of spiritual beings in Proclus’ metaphysics, I am intrigued that it can also be interpreted as a somewhat “deflationary” account of being, closer to Aristotle, and far removed from later notions of pure abstract existence. We can’t begin to have an account of being, without also having an account of life and intellect. With his endorsement of a One beyond “being”, Proclus had no need for a commitment to a notion of pure “being”.

What Would Kant Say?

Kant famously put strictures on metaphysical speculation. Sometimes it sounded as if he intended to abolish metaphysics altogether, but I think his actual intent was a reform. What would he say about my recent dwelling on medieval debates about omnipotence? Perhaps the most obvious answer is that these all involve unknowable claims. But this might be proceeding too hastily. It was actually a tangent in a post on Kant’s notion of moral faith that got me thinking again about the first volume of Gwenaëlle Aubry’s “archaeology”, which led to my discovery of her second volume.

Aubry suggests that for Peter Abelard, actual good ethics are the most important thing in religion, more important than professing adherence to revelation. I think Kant would have been profoundly sympathetic to the broad spirit of this. Abelard seems to have held that ethical reason and revelation, properly understood, teach us the very same lessons. His faith was a moral faith, not the kind that claims to be a superior knowledge. Granted that saying is a special kind of doing and that what we say in life has a deep ethical importance of its own, it is still true that what we actually do in the general sense counts for more than what we say or profess.