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”.

Being and Essence

The early short work of Thomas Aquinas Being and Essence argued very influentially that the essence or “whatness” of a thing can be understood independent of its existence, and therefore its existence must be something separate from its essence. Aquinas’ fellow student of Albert the Great, Dietrich of Freiberg (1250-1310), held on the contrary that there is no real distinction between being and essence, and that they are only distinct by their modes of signification, or ways in which they are said of things.

Aquinas points out that although essence is also called form, properly speaking the essence of non-simple beings or “composite substances” not only should not be identified with matter, but also should not be identified with form. The essence of a composite substance must include both the form and the matter. However, according to Aquinas, the composite of form and matter still has to separately be given being or existence by the Creator.

In contrast to common neo-Augustinian views that were more sharply dualistic than Augustine himself, Aquinas advanced a distinctive variant of hylomorphism, or the interdependence of form and matter. “Through the form, surely, which is the act of the matter, the matter is made a being in act and a certain kind of thing” (chapter 2).

This is a novel formulation using Aristotelian vocabulary in a somewhat Aristotelian style, and it has a kind of intrinsic appeal. The hylomorphic and implicitly anti-dualist sentiment is admirable. The suggestion that “form is the act of the matter” is appealing in its simplicity, but I don’t find Aristotle using act to explain the relation of form and matter.

Aristotle leaves the relation of form and matter happily underdetermined. He is more interested in ranges of variation of concrete things than in propositions with all abstract terms, however intriguing. That through the act of the matter, the matter is made a being in act is an intelligible and interesting claim, but I don’t think Aristotle would have said that either.

The notion of “act” in Aquinas is moreover not the same as it is in Aristotle. As Gwenaëlle Aubry notes, pure act in Aristotle is a final cause only, and explicitly not an efficient cause, whereas pure act in Aquinas is action, which is precisely and primarily an efficient cause. Aristotle’s first cause is the good that attracts beings; Aquinas’ God creates beings from nothing.

Aquinas goes on to give a novel account of being, famously arguing that in God — but only in God — essence and existence are indistinguishable. God for Aquinas — “I am who am” — is pure Being. His essence is pure existence. He has no other essence, and alone of all beings essentially exists. All other beings get their being or existence from God, and therefore their essence is really distinct from their existence.

Aquinas’ teaching of God as pure Being has to be understood as deliberately counterposed to the neoplatonic One beyond being. It is also incompatible with Plato’s Good that is more ancient and powerful than being.

Dietrich of Freiberg made the Aristotelian point that being is said in different ways for different kinds of things. He argued against Aquinas that the essence of a thing refers to everything about it, just as its being does. A human and a human being, he says, are exactly the same thing. Essence as such already involves being, and there is no being that is not the being of some essence. There is a nice little French edition L’Être et l’essence (1996), edited by Alain de Libera and Cyrille Michon, that has Latin and French texts of both Aquinas’ and Dietrich’s works by this title, with commentary.

Dietrich’s own theology was a highly original Aristotelianizing Christian neoplatonism. He tended to identify God with the neoplatonic One. He was known for his interest in natural science, and developed a detailed, accurate account of the optics of rainbows. According to de Libera and Michon, he spoke of a kind of natural providence. Inspired by Arabic Aristotelianism, he developed an elaborate cosmological-ethical theory of creative intellect. He argued that the human intellect does not just passively receive images of things, but has an active, creative component.

Dietrich was in Paris in the 1270s. Without a doubt he later became a leading light of the German Albertism that de Libera and others have associated both with the so-called “radical Aristotelianism” condemned in 1277 and with the rise of German mysticism. His slightly younger contemporary Meister Eckhart is known to have been influenced by his work.

Beings

When I talk about beings, or us as beings, I mean this in a very ordinary, pre-philosophical way. It seems to me that to informally qualify as a “being”, something must have a degree of coherence; a degree of resilience or persistence in the face of change; and relations to other beings.

We might form a notion of something absolutely singular or self-contained, but it would not be a notion of a being. The classic notion of something absolutely singular was the One of Plotinus, which for him explicitly preceded all being. For Plotinus, we should only begin to talk about being when we have something that is “both one and many”.

If we speak of beings, it makes some sense to inquire about the being of beings. To me, though, this just means a higher-order consideration of the ordinary “being a being” of ordinary beings. It does not imply some very different “Being with a capital B” that gives being to all ordinary beings.

When Aristotle inquired about “being as being”, he reached two main conclusions. First, “being is said in many ways”. That is to say, being is not a univocal concept; it has multiple meanings. More profoundly, what we nonetheless informally call being itself is itself analogous to something that is nonunivocal rather than univocal. The non-self-containedness that seems to be characteristic of beings means that if we look closely, what we call individual beings do not have univocal identity, but rather are “identified” by a kind of family resemblance to themselves. Beings do not have sharp edges that would unambiguously separate an inside from an outside, and sometimes they change profoundly. Second, being a being nonetheless always involves being some way that is distinguishable from some other way. Calling something a being or saying it “is” in any sense thus expresses a kind of commitment on our part, and as Aristotle and Brandom would both remind us, the very nature of commitments implicitly commits us to abstain from or correct other incompatible commitments.

Being a being in whatever sense thus involves both a determinateness and an openness. Determinateness and openness in turn have to be understood in ways that permit their coexistence. (See also Equivocal Determination; Openness of Reason; Bounty of Nature.)

I want to say that everything important about being a being belongs in the register of “whatness”, or what was traditionally called essence. Contrary to the great arguments of Aquinas as well as to the 20th century mystique of existentialism, I don’t find value in an allegedly separate register of existence. Some people have argued that Aristotle did not have a proper concept of existence, as if this were a shortcoming. I find Aristotle’s direction of our attention to the “what” of being to be noninflationary in a quite salutary way. (See also Substance; Platonic Truth; Meant Realities.)

Ricoeur on Embodiment

I’m still working through the introduction to Ricoeur’s Freedom and Nature. Having said a bit about how he intends to adapt Husserlian phenomenology, here I’ll add a few notes on the impact of Ricoeur’s Marcelian concerns.

“[A]s we examine actual practice, the understanding of articulations between the voluntary and the involuntary which we call motivation, motion, conditioning, etc., becomes stymied in an invincible confusion…. The triumph of description is distinction rather than a reuniting leap. Even in the first person, desire is something other than decision, movement is other than an idea, necessity is other than the will which consents to it. The Cogito is broken up within itself ” (pp. 13-14).

Considerations like this are why I think it is actually more precise to speak more loosely of “subjectivity” rather than “a” or “the” subject. Ricoeur draws the consequence that “the Ego must abandon its wish to posit itself, so that it can receive the nourishing and inspiring spontaneity which breaks the sterile circle of the self’s constant return to itself” (p. 14). He then introduces Marcel’s point about the mystery of incarnation as the answer to the question “How can I regain the sense of being alternately given over to my body and also its master… if not by… attempts to identify with the definite experience of existence which is myself in a corporal situation?” (p. 15; emphasis in original). In a more Aristotelian way, I’ve been making a similar point by suggesting that the hylomorphic, form-of-the-body notion of “soul” makes a good top-level model for the subtleties of what I’ve been calling empirical selfhood. (See also Two Kinds of Character; The Ambiguity of “Self”.)

Ricoeur goes on to say “the concepts we use, such as motivation, completion of a project, situation, etc., are indications of a living experience in which we are submerged more than signs of mastery which our intelligence exercises over our human condition. But in turn it is the task of philosophy to clarify existence itself by use of concepts. And this is the function of a descriptive phenomenology: it is the watershed separating romantic effusion and shallow intellectualism” (p. 17). He goes on to identify this “region of rational symptoms of existence” (ibid) with the space of reason as distinct from analytic understanding.

As Aristotle might remind us, “existence” is said in many ways. I have issues with the use of many of them in philosophy, but I take Marcel’s use of this term in a different and much more positive way than those, as mainly emphasizing all the aspects of things that don’t fit into neat schematizations, and that Aristotle would say are not univocally ordered. Aristotle and Ricoeur both take an emphasis like Marcel’s and reinsert it into a broader context that includes a more positive role than Marcel himself found for developments of reason. (For more on the same book, see Phenomenology of Will; Ricoeurian Choice; Voluntary Action; Consent?.)

Marcel on Being

I’ve been looking at Marcel’s The Mystery of Being (1950). “[I]t is not possible to treat all experience as coming down in the end to a self’s experience of its own states…. we shall see… how difficult it is to succeed in getting a direct glimpse of whatever it is that we mean by self.” (Vol. 1, p. 63-64; emphasis in original). “I appear to myself both as a somebody and not a somebody, a particular individual and not a particular individual” (p. 106). “This self to which I have to be true is perhaps merely the cry that comes out to me from my own depths — the appeal to me to become that which, literally and apparently, I now am not” (p. 176). Properly speaking, we should not say that our self exists, as this would make it a thing among other things.

Marcel says Truth should not be reduced to what is the case; it is an illumination. He distinguishes between primary reflection, which is objectifying, and secondary reflection, in which we ourselves are part of the reflection. In secondary reflection, we are participants rather than spectators. For example, “my” body is not some thing that I have, but rather something in which I am involved. More problematically from this writer’s point of view, he adds that my body is to me a sort of “non-mediatizable immediate” (p. 135).

To be is to be in a situation, understood in the participatory rather than the objectifying sense. We navigate situations by active processes of recognition and reconnoitring. “[A] being that can say, ‘My situation’… is not… self-contained; on the contrary, such a being is open and exposed” (p. 178; emphasis in original). “My life infinitely transcends my possible conscious grasp of my life… fundamentally and essentially it refuses to tally with itself” (p. 206). We should not represent a life as a series of movie stills.

Being is also being with, or togetherness with others. “[I]ntersubjectivity plays its part also within the life of the subject, even at moments when the latter’s only intercourse is with itself” (p. 224).

We should distinguish between an object and a presence. A presence lies beyond the grasp of any possible prehension, and can only be invoked or evoked. A rose in a poem is present to us in a way that a rose in a seed catalog is not. A mystery for Marcel is something that transcends the realm of technical solutions, in that we cannot hold it at arm’s length and objectify it, because it involves our own very being. Every Marcelian “presence” is mysterious in this way. “A felt quality… is not a mental object” (p. 231). Truth is not a thing, but a spirit. It is in this sort of way, he says, that essence should be understood.

In approaching the question of what Being is, “I have to think not only for myself, but for us… for everyone who may have contact with the thought which is mine” (Vol. 2, p. 6). We must exorcize the ego-centric spirit. “A complete and concrete knowledge of oneself… must be hetero-centric” (p. 9). He contrasts “we are” with “I think”. “[T]he intelligible milieu… is only the projection on an ideal plane of what existentially speaking presents itself to us as the intersubjective nexus” (p. 12). “[I]t is literally true to say that the more exclusively it is I who exist, the less do I exist” (p. 38; emphasis in original). He equates a transcendental ego with solipsism, but says that Being is not reducible to intersubjectivity, either.

Ontology for Marcel is concerned with acts of judgment associated with the “is” of predication, rather than with objects. He contrasts the “fullness” of truth with “the hollowness of a functionalized world” (p. 47). Fullness is not to be confused with totality, and being cannot be reduced to totality. Any fullness of truth involves secondary reflection, from which we cannot separate ourselves as participants. Being cannot be indifferent to value. Faith must be distinguished from opinion; it is a matter of believing in, not believing that. Real prayer, he says, is possible only where intersubjectivity is operative.

A free act is one that “I come to think of, after the event, as having helped to make me what I am” (p. 131). “[W]e are concerned here with a certainty which I am rather than with a certainty which I have… I am a living testimony” (p. 144). Just as there is creative fidelity, there is creative testimony, but the creativity in question involves an active receptivity, not a simple production.

Marcel’s invocations of “being” and “existence”, as well as of “presence” and of “ontology” all seem rather different from the standard, representationally oriented usages of these terms, to which I have expressed various objections. He also did not engage in anything like Heidegger’s dubious historiography of a “forgetting of Being”.

Early in the book, he seemed to reject “what is” questions as inherently objectifying. I think that questions of what and why are most naturally treated as matters of open-ended interpretation, and that ontology, epistemology, and all manner of specific technical disciplines can be subsumed under hermeneutics, which is in turn subsumed under ethics. From my perspective, what Marcel would have regarded as objectifying perspectives can thus be subsumed in a way that undoes their objectifying character.

Although Marcel’s style of exposition and vocabulary are very different from Aristotle’s, the broad spirit of his perspective seems very close in important respects. To a greater extent than most other philosophers, Aristotle and Marcel each in their own way brought to the fore an emphasis on concreteness and the way we encounter things in life. (Marcel’s pessimistic view of “what is” questions is perhaps the most significant difference. Aristotle also did not have explicit analogues of Marcel’s “presence” and “mystery”.)

While I am uncomfortable with Marcel’s top-level characterization of my relation to my body as an un-mediatizable immediacy because I think it involves the mediation of something like the unconscious level of Kantian processes of synthesis, I very much like the ethical contrast of being and having that informs the details of his account of this. Marcel doesn’t explicitly say as I do that “being” is primarily an ethical concept, but his account seems open to such an interpolation. (See also Ricoeur on Embodiment; Platonic Truth; Meant Realities; Being, Consciousness.)

Efficient Cause, Again

Yesterday, I changed my thinking about Aristotle’s “efficient cause”, making a somewhat surprising connection to the modern notion of “structural causality”. Then I had to update my account of generalized unmoved movers to add a case for an unmoved efficient cause.

Aristotle’s whole framework of “causes” (answers to “why” questions) is often misunderstood, and it is especially bad with the so-called efficient cause. A quick web search on the latter turns up mostly accounts that are just wrong. (A wonderful exception is the outstanding article in the Stanford Encyclopedia of Philosophy).

At Physics 195b22-25, referring back to an earlier example of a man building a house that was initially said (metonymically, it turns out) to be an efficient cause, Aristotle wrote (Complete Works, Barnes edition) “In investigating the cause of each thing it is always necessary to seek what is most precise (as also in other things): thus a man builds because he is a builder, and a builder builds in virtue of his art of building. This last cause then is prior; and so generally.” So it is the art of building — not the carpenter or the hammer or the hammer’s blow — that primarily “builds” the house (i.e., governs the details of the process its construction), and is properly (not just metonymically) called its efficient cause. Once again, for Aristotle it is something at the level of adverbial detail — not the coarse level of agents or action — that is most important.

Having said the other day that Foucaultian discursive regularities are a kind of efficient cause like the art of building, it occurred to me they are also a good example of structural causality, and then that one might say the same about, e.g., the art of building.

Previously, I had been thinking about the efficient cause as functioning like a sort of catalyst. This relatively modest role had led me to privately think of the efficient cause as an “accidental” cause (i.e., one not really contributing to the essence of the thing).

This was at the opposite extreme from the tendency of late scholastics like the great Jesuit Francisco Suárez (1548-1617) to make efficient causes paradigmatic for causes in general, conceived in a proto-modern sense of being responsible for the fact of a thing’s being or existence rather than for the manner of its being, and as involving an “influence” from an agent rather than reasons. (In this context, ends or “final causes” were also reduced to mental intentions of a natural or supernatural agent, as al-Ghazali (d. 1111 CE) had done earlier, quite contrary to Aristotle’s own non-mental account. It was this mentalist reinterpretation that was the real target of Spinoza’s eloquent polemic against against teleology.) There is a nice article by Stephan Schmid on these issues in Suárez.

Anyway, an efficient cause as a point of application of structural causality clearly has a much bigger role to play in determining the detailed nature of a thing than the purely external one of a mere catalyst. (I am using the word “nature” here in a sense broader than Aristotle’s, similar to essence but particular to things that come to be, whereas Aristotle further limited it to nonartificial things, which he thought all contained at least a rudimentary internal principle of motion not shared by artificial things.) On my new account, the efficient cause also exemplifies the interweaving of Aristotelian essence with accident or contingency, due to the role of the semantic materiality as well as form of the means of realization of a nature that is its efficient cause.

This is also more conformant to the idea that all Aristotelian causes are supposed to contribute to explaining the natures of things. Ironically, my previous “catalyst” view made the efficient cause a kind of exception that looked more like the sort of cause of existence I have generally been arguing is un-Aristotelian. As a point of application of structural causality, an efficient cause now fits the general pattern of explaining natures, rather than the mere factual existence of things with natures more or less taken for granted.

Being, Existence

Aristotle should not be lumped together with the later trend that treats ultra-abstract (or singular) terms like “being” or “existence” as having deep philosophical significance.

He famously wrote that “being is said in many ways”.

Though he did twice mention a possible “science” of being qua being, in both of the books of the Metaphysics in which he starts to discuss it, anticlimactically the only content he gives it is the principle of noncontradiction, behind which lies a kind of ethical obligation to respect material incompatibility of meanings. Aristotle’s sole explicit criterion for “being qua being” is passing the test of this respect for material incompatibility. To successfully pick out a “being” or meant reality, a concept or concept use must respect material incompatibility. The importance of this respect is shown by Aristotle’s very uncharacteristic display of anger at the Sophist who tramples on such respect.

He prefers to direct our attention to “beings” rather than to singular “Being” or a generic “being of beings”. The aspect of picking out a “being” by its specific “essence” is essential to its being a being. “Essence” — understood as constituted through intelligible distinctions, rather than pre-given — is far more important for Aristotle than the bare fact of so-called “existence”. (Facts are important too, but much more for their meaningful content than for any sheer “facticity”. For Aristotle, something like facticity as such would be a subordinate aspect of materiality.)

Metaphysics was a title assigned by a later editor to a collection of manuscripts of different dates. Commentators debated about its true subject matter. The idea that metaphysics equals ontology — opposed in the middle ages by the highly influential Averroes — became dominant only relatively late. The equation with ontology was especially associated with projects significantly different from Aristotle’s, like those of Avicenna and Duns Scotus. Eventually it became canonical with Wolff.

Heidegger wanted to distinguish Being from beings, and spoke about a forgetting of Being after the pre-Socratics, who allegedly had it in view. I say good riddance, if there ever was such a thing.

It is true and good that there is no Being in Aristotle. He correctly said “being” is not a unitary concept. The core of the Metaphysics is instead about what he calls ousia, or what answers the question “what a thing was to have been” — i.e, form or essence, not being as existence in the common modern sense. He also mentions other sorts of being, such as being the case or being true.

Kant correctly pointed out that existence is not a property. Hegel in the Logic correctly said Being is empty and equivalent to Nothing.

In Greek, “existence” literally means standing out. To “exist” in this sense is to be determinately distinguishable or, in modern terms, to be a subject of some existential quantification, as when we formulate a mathematical proof that for any given A with specified properties, there “exists” (i.e., we can pick out) some B or a unique B with specified other properties. Existence in the sense of standing out is always relative to something else.

An abstract, nonrelative concept of “existence” is not needed in order to express real-world constraints and determinacy. Aristotle for instance uses more specific and supple concepts for this, like energeia (“at-work-ness” or actuality) and dynamis (potentiality).

The notion of existence as a nonrelative property of a thing, I suspect, owes something to the concern of medieval theologians to prove such a property for a nonobservable entity.

If something is normatively important, it is so regardless of whether it “exists” or is ideal or virtual. What is practically important is not abstract existence but practical difference, normative importance and conceptual articulation. (See also Form, Substance; Aristotelian Dialectic.)