“We Understand Him Even Better Than He Understood Himself”: Kant and Plato on Sensibility, God, and the Good

1 Introduction

In this article, I argue against Immanuel Kant’s assertion that he understood Plato “even better than [Plato] … understood himself” (A314/B317).^[1] Kant’s critical remarks aim to expose Plato’s alleged forgetfulness of the importance of the sensible, experiential world. However, I show that Kant’s own interest in the role of sensibility is rather in agreement with a reading of Plato that does not make the latter out to be a metaphysical realist or rationalist and a thinker who places the intellect over and above the senses. Thus, Kant’s view of Plato is one-sided. If we allow a different picture of the dialogical relationship between the sensible and the noetic to emerge – a picture which I offer in this article – then we can establish a much greater affinity between Plato’s and Kant’s thinking than Kant himself is willing to admit.

In terms of the relationship between the sensible and the ideated, Kant takes his own work to suture the divide between the two, while holding fast to a metaphysically sound articulation of the role and place of the ideas. Plato, in Kant’s view, went much too far in the direction of a fanciful flight where understanding directs itself not to sensibility, thereby structuring experience, but out and away – toward the ideated, thus producing not concepts valid for experience, but merely phantasms. Instead of allowing the understanding to produce amphibolies (A260/B316) or letting reason generate illusory ideas (A297/B354), Kant confines the understanding to sensibility, thereby limiting its scope, but ensuring the validity of its concepts. Theoretical reason and its ideas also receive a narrower playing field in Kant. He restricts the valid use of theoretical reason to analyzing the understanding, while simultaneously directing the understanding to work on sensibility.

However, and this is my claim, the proscription of the invalid use of reason as well as a thoroughgoing questioning of a fundamental distinction between the intelligible realm and the world of sense is already inscribed into the dialogical conversations of Plato’s characters. In other words, the type of questioning of the objective status of ideas that Kant carries out and the undoing of the metaphysical dualism – in my reading – is already indicated in Plato’s dialogical exchanges. However, and likewise, a basis for deriving dualistic and idealist systems is also readily available in the very same dialogues. Overwhelmingly (albeit not without important exceptions), the history of interpretation all but identifies this latter possibility of understanding the metaphysical passages in the dialogues with what Plato himself thought. In my own engagement with Plato’s thinking, I take up the interpretive tradition that follows very closely the dramatic and literary structure of the dialogical exchanges in order to avoid imposing doctrinal views onto Plato’s texts.^[2] This method allows me to show the way in which Kant’s own arguments against dogmatic metaphysics can be used to further develop, but do not contradict, Plato’s thought.

In Section 2 of this article, I show that Kant and Plato are closer on the question of the status of the sensible than Kant believes. To accomplish this, I analyze the discussion of the Good in the Republic in order to stress Socrates’ emphasis on the role of sensible images in that discussion (508e-509c), and I also engage with the Phaedo and the commentators who argue against the traditional view of Plato as proposing a Theory of Forms or Ideas. In Section 3, I offer a comparative analysis between the Good of the Republic and Kant’s view of God. This allows me to retrace the steps of Kant’s thinking about regulative ideas, and especially about the Ideal of reason, and to connect it to the discussion of the Good in Plato’s Republic.

2 Platonic Roots of Kant’s Ideal and the Ίδέα of the Good in the Republic

Differentiating between Kant’s own metaphysics and the metaphysics which Kant ascribes to Plato, David A. White writes that Kant’s problem with Plato’s metaphysics was that “in positing the ideas alone as the object of knowledge, Plato overlooked what is just as essential to knowledge – sensory intuition.”^[3] On Kant’s own view, and as his first Critique works to show, ideas or pure concepts of reason are perfectly acceptable, but only in so far as we acknowledge that these arise on the basis of our understanding, which in its stead cannot give us any knowledge, unless it (and also in it’s a priori function) is limited by our sensible intuition. In his engagement with Plato, Kant appears to adopt a Platonist’s view of Plato. In other words, Kant denies to Plato that the latter paid sufficient attention to the importance of the sensible world. Manfred Kuehn reports, “Kant seems to have read Plato himself,”^[4] but as Kuehn conjectures, relying on Michael Gill’s evidence, Kant is also likely to have been familiar with Plato through Cambridge Platonists such as Ralph Cudworth. The latter combined his interest in idealism, which he saw in Plato, with monotheism. Manfred Baum observes, “Kant never attributed the two-world doctrine to Plato himself, neither in the [1770] Dissertation, nor in his later work. This is all the more remarkable, since Kant’s main source, Brucker (who was aware of the doctrine’s origin in Philo of Alexandria’s text, De opificio mundi) nonetheless attributed it to Plato.”^[5] However, Kant takes it to be the case that Plato’s philosophy went much too far in positing the supremacy of the intelligible over the sensible (“Plato abandoned the world of the senses because it posed so many hindrances for the understanding” A5/B9). Thus, Kant must have thought that Plato had these two elements – the sensible and the noetic – and that he set the latter over and above the former. Kant’s own formulation of the pivotal moments of a metaphysical investigation appears already in his 1770 Dissertation.

In Kant’s inaugural 1770 Dissertation thesis, De mundi sensibilis atque intelligibilis forma et principiis, Kant retraces the view of metaphysics according to which God is both an origin of perfection and the principle of knowledge of any perfection.^[6] Kant works to show that “although, God, as the ideal of perfection, is the principle of cognizing, He is also, at the same time, in so far as He really exists, the principle of coming into being of all perfection whatsoever” (2:396).^[7] This view concerning the reality of God’s existence is problematized eleven years later in the first Critique, where in the Transcendental Dialectic (A570/B598-A583/B661), Kant tells us that “the object of reason’s ideal, which is to be found only in reason, is also called the original being, … the highest being, … and the being of all beings” (A578/B606-A579/B607). Kant goes on to say that this signifies merely a “relation … of an idea to concepts” (A579/B607). In other words, all of these designations are necessitated by reason, but cannot lead to the inference of an existing being. Instead, reason in its search for the ultimate unitary ground of concepts attempts to arrive at an unconditioned condition. As Kant has it, the “proper principle of reason in general (in its logical use) is to find the unconditioned for conditioned cognitions of the understanding, with which its unity” – the unity of the understanding – “will be completed” (A307/B364). Commenting on this propensity of pure reason, which works upon the concepts of understanding, but which is not itself limited by sensible experience, Michelle Grier writes that the “problem is that the ‘unconditioned’ is never actually given, and the assumption that it is instantiates the transcendental illusion that motivates transcendent metaphysics. Moreover,” Grier continues, “rather than being an avoidable or merely logical error, transcendental illusion lies in the very nature of reason. It is, indeed, Kant’s efforts to link up traditional rationalist metaphysics with this unavoidable demand of reason that characterizes not only the critique of the Ideal, but all of Kant’s criticisms throughout the Dialectic.”^[8] It is in the nature of theoretical or pure reason to aspire to such arrangements of thought, which do not correspond to anything really existing while presenting these surreal or illusory phantasms as real beings. In the first Critique, then, God serves as this focal point toward which reason strives for the highest unity. However, this unity is ideated, and it is not a really existing being, but an Ideal that reason gives to itself.

Kant’s presentation of God – even if not as a real, but as a necessary and ideal or an ideated relation – follows closely Socrates’ description of the Good in Bk. VI of the Republic where at the end of one of the most widely commented on passages in Plato, Socrates claims that the Good lies beyond Being (509c). In order to establish important affinities between Kant’s own view and the discussion of the Good in Plato, I offer my analysis of the Republic passage (508e-509c). There are several other dialogues of Plato that are often taken to indicate that, for Plato, the intellect (νοῦς) and reason (λόγος) have priority over and above the senses (e.g., Meno, Timaeus, Phaedo, Phaedrus, Symposium). All of these dialogues, in my reading, can be interpreted in such a way that the relationship between the sensible and the intelligible is reconfigured in favor of underscoring their equal significance. However, guided by my interest in Kant’s engagement with Plato, in this article, I will focus on the discussion of the Good in the Republic.^[9]

In the Republic, the Good appears to be the source of existing beings as well as of our epistemic access to them (509c).^[10] However, what Socrates says while leading us up to this insight, introduces another unity, i.e., between the intelligibility and sensibility in relation to the good. My reading of Socrates’ analogies and descriptions in 508e-509c runs counter to the most widely accepted take on this passage as well as on Plato’s metaphysics.^[11] In other words, I aim to move away from the position according to which Plato sought to install ontotheology or that makes him a proponent of a rationalist metaphysics that downgrades the power and the role of the senses. In the lines from the Republic, which I take as indicating the critical importance of the sensible faculty to our capacity to know the truth, Socrates, addressing Glaucon, recommends that “you must say then that that which installs truth within the graspable things [γιγνωσκομένοις] and gives power to the one who reckons [γιγνώσκοντι] is the look [ἰδέαν] of the good [τοῦ ἀγαθοῦ]” (508e). From the start, the description that Socrates gives to the Good in this very famous passage (the description, which as Marina McCoy contends, holds fast to images and image-making) retains the relationship between the senses and the mind.^[12] This relationship is downplayed if we follow the translations of “ἰδέα” as “idea” or mental “form.” The word, “ἰδέα” just as readily, if not more so, admits of being rendered as a “look” or a visible and sensible “form” or “shape.”^[13]

It is critically important to maintain the tension between the sensible and the noetic that Plato’s language offers for our consideration. If we opt to turn a blind eye to this and other tensions, then attractively coherent theoretical structures may arise on the basis of the most famous dialogical passages, while critical insights into the philosophical thought with which these passages present us are likely to fall away. One of such key insights is the fact that this central passage does not privilege the noetic over and above the sensible. If anything, it holds the two together in a non-hierarchical relationship because here Socrates says that the truth of things that become available for our circumspection as well as the power to reckon with these things comes from the ἰδέα – or the sensible look – of the Good (or from the visible aspect that is good).^[14] The next line which Socrates offers can also be interpreted in a direction that indicates the indispensability of the sensible. Namely, Socrates’ recommendation to “[b]e mindful further to perceive it [the look of the good] as being the cause of knowledge [ἐπιστήμης] and truth [ἀληθείας] of the known” (508e) states that the causal relationship runs from the palpably given, i.e., from the look of the Good to the possibility of knowledge and truth.^[15]

To put it in stronger terms, it is the sensible look of things, which discloses and gives us access to the possibility of knowledge and truth about the world. Socrates exhorts Glaucon to perceive the bountiful self-presentation of appearing things – whatever value we may assign to them upon examination – as being the look of the Good or as the Good that the appearing world is in virtue of its unfolding before us. The alethurgic and epistemic access that we have to the world is not indexed to some supra-experiential reality.^[16] Instead, it is made possible by the play of ideality and actuality, which both are responsible for and co-constitutive of our experience. The latter transpires for beings like us on the basis of our sensible immersion in the world. Socrates, then, specifies the relationship in which both knowledge and truth stand to the Good. He does so by means of yet another visual analogy.

As for the knowledge [ἐπιστήμης] and truth [ἀλήθειαν], just as it is right [ὀρθόν] to hold an opinion [νομίζειν] of light and sight to be sunlike, nonetheless, to take it [ἡγεῖσθαι] that they are the sun is not right [οὐκ ὀρθῶς]. Likewise, to hold an opinion [νομίζειν] that those others both are the good-look-alike [ἀγαθοειδῆ] is right [ὀρθόν], but it is not right [οὐκ ὀρθόν] to take [ἡγεῖσθαι] either of them as the good [ἀγαθὸν], but to the way of the good [ἀγαθοῦ ἕξιν] accrues still greater honor. (508e-509a)

Here too Socrates never departs from language that indicates a palpably given, perceptible character of things. However, now, it is knowledge and truth that are described as having the look of the Good or being Good-look-alikes (ἀγαθοειδῆ).^[17] The definitive connection between the good, knowledge, and truth is established by means of a likeness that holds fast to the sensible aspect of things. Next, Socrates joins the ontological and epistemic registers. He assigns both the being of living things and our power to know them to the Good.

You must say then that the sun not only installs the power to be visible within the visible things, but also the power of becoming, growth, and nourishment, although it itself is not in becoming. … Likewise, it should be said that the graspable things [γιγνωσκομένοις] not only come to be reckoned with [γιγνώσκεσθαι] by being proximally near the good, but that also their existence and being belong to it. Although the good does not exist in being, but exceeds being in dignity and power. (508e-509c)^[18]

Importantly, and as Socrates stresses, the Good itself is not accessible for our circumspection – intellectual or sensible – but lies outside of Being (509b).^[19] We simply have no access to the Good as such, but only to the world that unfolds for us in its sensible aspect, and which can be known in truth not merely by the mind, but also through our sensible and sense-dependent openness. Although it is the case that Socrates places the Good over and above the sun and even sets the good beyond Being, the entire presentation of the Good rests on a set of visual analogies.^[20]

The conversation about the Good and its relation to the world of becoming is nuanced. The exchanges about the Good proceed by way of several analogies, which Socrates works to modify. These modifications change the meaning of the elements that make up the analogies. I offer a schematic presentation of the passage. The analogy that Socrates makes at 508b-c is as follows: (I) the Sun: to the Visible Realm: Sight: Seen Things:: Good: Intelligible Realm: Intelligence: Intellected Things. In the Greek, this latter term, “intellected things,” says “τὰ νοούμενα.” Then, just a few lines later, at 508e a refigured analogy emerges and we have (II) the Sun: Visible Realm: Sight: Seen Things:: Being (τὸ ὄν) and Truth: Intelligible Realm: Intelligence: Intellected Things. Being or τὸ ὄν and Truth or ἀλήθειά replace the Good of the first analogy. Then, we have one more alteration. At 508e, Socrates says that (III) the ἰδέα of the Good: Knowledge (ἐπιστήμη) and Truth (ἀλήθειά):: Sun: Light and Sight. In the first reformulation of the initial analogy (II), the Good, which is supposed to be beyond all Being, gets substituted with that very element, i.e., Being, which it allegedly supersedes. Thus, in order to arrive at the metaphysical structure, where the noetic dimension grounds and also dominates the sensible world, the very condition on which the primacy of the ideal depends (i.e., that the Good remains beyond Being and only the Idea of the Good serve as a standard of truth and knowledge) is severely undermined. The second substitution (III) entails an elimination of Being, in place of which comes knowledge. In this move, the ideality of Being, which stood as co-primary with truth, is replaced with the mind-dependent strictures of knowledge. It is at this step that Socrates introduces the ἰδέα of the Good, which now neatly fits on the noetic side (i.e., the so-called “Idea” of the Good: Knowledge: Truth) of the analogy on the other side of which now stands Sun, Light, and Sight. In this last iteration, the analogy looks not only noocentric but also anthropocentric. The Visible Realm as well as the Seen Things fall out from the side that initially contained these sensible elements. It is as if not only the Good and Being, but also the very world of the many different beings got erased and we are left with nothing to see, know, or discover the truth about. In this surreptitious set of substitutions, I see Socrates’ attempt to call our attention to the fact that we go awry if we attribute a privileged place to the mind setting it over and above the senses (and also if we set the supra-sensible reality over and above the experiential world).

This is a trope that repeats itself time and again in the dialogues (e.g., the sensible and the intelligible elements in the Phaedo or the non-lover and the lover of the palinode in the Phaedrus or the discussion of the “lovers of sights” and the “philosophers” of the Republic 475d-476a), i.e., Plato carries out a set of divisions and opposes the divided elements. He then recombines the elements from the opposed sides so as to hierarchize them. Some elements end up being privileged and others devalued. However, these are spurious hierarchies. I propose that they are established, precisely, for the sake of our noticing their spuriousness and realizing that hierarchical privileging and preferential treatment of certain things just because they are identified with philosophers or a philosophical way of life (on the surface of the dialogical exchanges), must be set aside. For one, this very view of hierarchization is destabilized by Plato’s own writing. In the Republic, and as if to remind us of the importance of our sensible attunement to the world, Socrates reintroduces our connection to the senses in conclusion to his analogies when he finally arrives at the ἰδέα of the Good. If we translate ἰδέα here as “idea” or mental “form,” we end up with noo-centricism: a conclusion which I wish to avoid. The point is not to say that the senses accomplish the work of understanding or that the mind is unimportant. The point is to bring the sensible dimension back in its full significance to the work of our thinking and theorizing.

The traditional way to interpret Socrates’ analogizing is to say that we must take ἰδέα less literally (i.e., to mean not “look” but “idea”) and to agree with the overwhelming view that Socrates is privileging the mental and ideated elements of cognition over and above the senses (and also that he sets the Forms or Ideas as origins of the experiential world).^[21] We would then follow the familiar trope of the standard interpretation of the relationship between the sensible and the intelligible that is given to Plato’s metaphysics.^[22] Adherents of this view hold that we can access ideas through thinking. Moreover, the senses both depend on the intelligible and also the latter is set over and above the former in terms of their value and importance.^[23] The more traditional interpretation of the relationship between the mind, the ideas, and the senses runs along the lines of Michael Rohlf’s gloss:

Plato conceives of ideas (or forms) as extra-mental entities that exist in a separate intelligible realm and govern the structure of the visible world. For Plato, ideas are intelligible archetypes of things in the visible world: they play the metaphysical role of causing sensible things to exist and to have whatever properties they have, and the epistemological role of enabling us to acquire knowledge of sensible things through our grasp of ideas.^[24]

This view claims that 1) there are ideas that do not come from human minds; 2) that these ideas exist outside of the world, but that 3) they nonetheless serve as the origin of the world as well as 4) of the human capacity to know it.

Given my interest in this article, which is to show that Kant’s view regarding the co-primacy of the sensible and the noetic agrees with rather than runs counter to what we find in Plato, I will not be offering an extensive critique of the standard take on Plato’s metaphysics. However, such critique has been offered by John Sallis, Drew A. Hyland, Stanley Rosen, and others. As I argue in my analysis of the Phaedo, it is utterly erroneous to attribute to Plato a two-world dualism or any other stratification between the world, as we know it, and some otherworldly beyond. This is the case not because I aim to prove that somehow the world of ideas and this world are one, but because there is no such thing as a world of ideas or forms that stands above and beyond this world.^[25] John Sallis, also commenting on the Phaedo, points out the problem with taking such deeply sense-bound things as Bigness, Health, and Strength (65d-66a) – the very things that are examples of what traditionally is taken to designate ἀυτά τά ἴσα – as genuine representatives of and elements that support Plato’s theory of forms. Furthermore, Drew A. Hyland offers a critique of the ingrained view regarding Plato’s Theory of the Forms. Hyland argues that it is anachronistic to assign to Plato, an ancient author, any “quasi-scientific” views or any such systems as those that come to us from much later thinkers, like Hegel.^[26] Citing several scholars who also disagree with the canon on the Theory of Forms (e.g., W. Wieland 1982, John Sallis 1975, Stanley Rosen 1983, 1988, 1991, and Charles Griswold 1988), Hyland submits that

[w]e must make the stunning admission that this so-called theory … so closely identified with Plato is not given a single confirming instance in all the dialogues. Despite initial appearances (that “friendship” is the topic of the Lysis, “the Equal Itself” is discussed in the Phaedo, “what piety is” is the theme of the Euthyphro, and so on), no character in any dialogue ever learns and articulates for us the knowledge actually gained from an insight into a specific idea. All discussions are generic and programmatic.^[27]

Hyland’s point is that it is a hasty generalization to lump all of the instances of seemingly similar discussions and on the basis of this aggregation claim that Plato has a Theory of Forms or Ideas and that, moreover, the latter is the kernel and main idea of his philosophy. Instead, we ought to exercise much greater care as interpreters of the dialogues and approach each instance of the mention of these looks (είδη) or themselves (ἀυτά τά ἴσα) and situate them within – not systematic, but dramatic – structure of Plato’s dialogical play.^[28] I agree with Hyland et al. regarding the misplaced, albeit ingrained, dogmatic faith on the part of the majority of Plato scholarship regarding the status or even the existence of the so-called Theory of Ideas or Forms. However, I cite Rohlf on Plato above because his view represents what Kant himself is criticizing. If on a traditional interpretation, Plato holds that the noetic supersedes the sensible in making possible our cognition and knowledge of the world, then this is precisely what Kant sees as the problem with Plato’s metaphysics. Namely, Kant impugns to Plato that he

abandoned the world of the senses because it posed so many hindrances for the understanding, and dared to go beyond it on the wings of the ideas, in the empty space of pure understanding. He did not notice that he made no headway by his efforts, for he had no resistance, no support, as it were, by which he could stiffen himself, and to which he could apply his powers in order to get his understanding off the ground. (A5/B9)

According to Kant, Plato sought to move beyond the senses and the sensible world in order to reach the ideas themselves or ideas as such – as objects of some possible experience. The notion of ideas themselves as empirically real entities would be wrongheaded, as would the notion of knowledge of things in themselves. Kant is criticizing Plato, not for thinking of ideas, but for suggesting they can extend our knowledge of the empirical world through pure reason or intellectual speculation. However, the issue that Kant takes with Plato falls away if we observe that such key passages, as the central discussion of the Good in the Republic, retain the significance of the sensible instead of abstracting away from and denigrating it in favor of the noetic. By this, I do not mean that we find in Plato the same robust and fully developed theory of sensibility as we do in Kant. For one, Kant draws a difference between the a priori forms of our sensible intuition, i.e., space and time, and the matter of intuition, which comes from experience. Moreover, Kant develops metaphysics, which is directed at providing an analysis of the a priori elements of our cognition or an inventory of pure reason (A xx). I am not claiming that we find the same transcendental strain in Plato’s thought. What I wish to make clear, however, is the fact that Kant was mistaken to attribute to Plato a metaphysical system of ideas that are supposed to be the condition of knowledge of the things in themselves, that are unbounded by experience, and that do not abide by the strictures of sensibility while at the same time constituting a metaphysical reality. In other words, if knowledge of ideal entities is requisite for knowledge of the (empirical) world, then Kant is raising both a metaphysical and epistemological objection against Platonism. There is a way to read Plato whereby the senses and the intellect do not stand in a subordinated relationship to each other. In this alternative reading, the sensible is interwoven with the intelligible and the two are equiprimordial in terms of our access to the world. If we admit that the sensible dimension of experience is just as important as the intellect to our discovery of the world, the possibility of knowledge, and our encounters with truth, then we have an alignment between the sensibility and the intelligibility in Plato, which Kant seeks to establish in his own philosophy.^[29]

Kant presents the basic relationship between the sensible and intelligible in Section II of his 1770 inaugural dissertation. Thus, one of the most important differences that Kant draws already in this inaugural thesis is the difference between sensibility and intellect. In the Critique of Pure Reason, this difference is at the core of Kant’s analyses of cognition in the Transcendental Aesthetic and the Transcendental Analytic. Describing our sensible faculty Kant states that the “capacity (receptivity) to acquire representations through the way in which we are affected by objects is called sensibility” (Die Faehigkeit (Rezeptivitaet), Vorstellungen durch die Art, wie wir von Gegenstaenden affiziert werden zu bekommen, heisst Sinnlichkeit, A19/B33). Our intuition or Sinnlichkeit – that power by which any object is related to our cognition immediately – is a sensible intuition. For Kant, our intuition is not intelligible, while what is intelligible is not immediate. The latter is always given to us through a mediation by the concepts of thought; that is, by the categories of our understanding. Kant confirms this when he writes “all thought … must ultimately be related to intuition, thus, in our case, to sensibility, since there is no other way in which the objects can be given to us” (A19/B33). Objects do not affect the thought right away. Understanding and its concepts are active – they act upon and organize that which is given in the sensible intuition.^[30]

I do not wish to stretch the analogy between Kant and Plato too far and imply that we find a similar arrangement between the a priori elements of cognition and our experience of the world in the Republic. My claim is that in Socrates’ discussion of the Good, our access to the world is tied to our receptivity to the sensible looks or forms that make it possible for us to attain knowledge and truth about the world. In my reading, both Plato and Kant hold fast to this commitment to the importance of sensibility, even if in Kant’s own assessment, Plato fails to do so. In other words, for Plato, just as for Kant, there is but one world in which we experience the sensibility and intelligibility of entities. All our empirical knowledge of the world depends on the representation of intuitions according to an intellectual categorization under pure concepts. So, just as Kant insists that the concepts are not in another world, but apply to this one, likewise, what Socrates shows is that the division between the ideas and the beings is in us and it is a matter of the polyvalence of the look and idea. This is not, however, a division between worlds or realities; let alone such realities as can be experienced by our embodied selves – on the one hand – and our disembodied soul, on the other. This latter world, on my interpretation, is at best, a charm meant to alleviate our fears of mortality; or our distrust of the μορμολυκεῖον of our finite life (Phaedo 77e).

3 God as the Ideal of Reason and the Good that is Beyond Being

In my reading, both Kant and Plato realize the significance of our sensible immersion in the world. Likewise, both indicate that our thinking cannot produce meaningful theories about that which does not actually exist. God, for Kant, and the Good, in the Republic, may serve to orient our thinking, but they lie outside of the world of existing beings that we comprehend in thought.^[31] For Kant at least, God cannot be Dasein or Nichtsein; but must be merely possible in the sense Kant says at A568/B596. He says that the Ideal as opposed to an Idea of Reason is “something that seems to be even further removed from objective reality.” In the case of the Ideal of Reason, we have reason’s operation on its own ideas. In the course of this operation, our reasons is producing the “idea not merely in concreto but in individuo, i.e, as an individual thing which is determinable, or even determined, through the idea alone” (A568/B596). The result is that based on the ideas that admit of highest universality, reason is aiming to absolve itself from everything. It seeks only to perform its own formative work, and through this formation, to produce not merely another concrete idea, but a being – an individual, as Kant says – the highest being, which is God. However, and despite the history of religious thought, existence cannot be attributed to this highest being. Kant further states that “what is special about an idea [e.g., as of God] is just that no experience can ever be congruent to it. The transcendental idea of a necessary all-sufficient original being is so overwhelmingly great, so sublimely high above everything empirical, which is at all times conditioned, that partly one can never even procure enough material in experience to fill such a concept” (A629/B649). We simply can’t have an object of experience corresponding in its existence to the idea of a supreme being.

At A593/B621 – A595/B623, Kant shows why it is important to remember the difference between a pure judgment about something and an affirmation of the existence of that something. His example is the invalid attribution of existence to a triangle.^[32] The proof hangs on identifying essence with existence. It is the essence of a triangle to contain three angles amounting to 180 degrees and in so far as we are talking about such a figure as admits of this definition, we are also describing the existence of the triangle. The essence of a triangle is the existence of a triangle. Mutatis mutandis, the essence of God is existence. Kant undoes this by saying that just because we can have an a priori concept of a geometrical figure, we do not yet have its existence following necessarily. Existence, in this case, means Dasein, which is the second category under the heading of Modality. Existence is not indicated in the constitution of the appearing object. According to the principles of pure understanding, existence is a modification of our regard, of our phenomenological attitude, or of our cognition in respect of the object. All of this is to say that we are making an invalid inference, if we attribute necessary existence to anything merely on the basis of the pure conceptual definition or determination of that something. Be it a concept of a triangle or of God. For Kant, we can’t “infer immediately from the possibility of the concept (logical possibility) to the possibility of the thing (real possibility)” (A596/B624). However, as far as operations of practical reason are concerned, “[t]he moral Law … must … lead to … to the presupposition of the existence [Dasein] of a cause adequate to this effect; i.e., it must postulate the existence of God [die Existenz Gottes], as belonging necessarily to the possibility of the highest good (the object of our will which is linked necessarily with the moral legislation of pure reason)” (Critique of Practical Reason 124). And yet, the existence of such a being remains a postulate, but not an experientially objective reality. As Kant says, “it must be noted carefully here that … moral necessity is subjective, i.e., a need, and not objective, i.e., itself a duty; for there can be no duty whatever to assume the existence of a thing (because doing so concerns only the theoretical use of reason)” (125).^[33] Thus, our thoughts about the Good or God are real, but neither the idea of the Good (as in the Republic) nor the idea of God correspond to possible objects of experience, i.e., as belonging to the world of our experience. To assume that they do is to be utterly mistaken.^[34] Instead, what we have in these designations is an ideated or ideal reality – a reality, that Kant attributes to the unifying and grounding activity of reason. As Baum sees it, for Kant, “God is … an ideal in that He is the principle of cognizing the perfection of finite things – something that does not exclude his real existence as the cause of the world (Weltursache).”^[35] Although this view can be ascribed to Kant’s 1770 thesis, the first Critique offers a different presentation as far as the reality of God’s existence is concerned. Postulated existence of something as a cause does not necessitate its substantially real existence (Dasein), let alone its empirical givenness (e.g., A220-221/B268; A594/B622).

For example, the transcendental unity of apperception (B157-159 and esp., fn. to B157-158) – an absolutely crucial element of Kant’s metaphysics – is the condition on which I can say that my representations are mine; that they belong to me. Although the transcendental unity of apperception is the ground and cause of the cognition “I am I,” it is not real in a sense that my experiences of things about which I think or which I see and do are real. Thus, on the grounds of the first Critique and as far as the theoretical use of reason is concerned, we cannot say that God really exists or has a Dasein. However, the limitations that Kant places upon theoretical reason in the first Critique clear up the use and activity of reason in a practical sense. Thus, in the Critique of Practical Reason, morality and virtuous action are tied in their possibility to the existence of God as their ground (5: 125; 5: 145-46). If we maintain this causally efficient, but not empirically real status of God for Kant, then this strengthens the affinity between Kant’s God in the first Critique and the Good in the Republic.

In this context, Kant explicitly mentions the Republic in the first Critique. Kant engages with this dialogue at the start of the Transcendental Dialectic where he writes that

Plato noted very well that our power of cognition [Erkenntniskraft] feels a far higher need than that of merely spelling out appearances according to a synthetic unity in order to be able to read them as experience, and that our reason naturally exalts itself to cognitions [zu Erkenntnissen] that go much too far for any object that experience can give ever to be congruent, but that nonetheless have their reality and are by no means merely figments of the brain. (A314/B371)

Here, Kant endorses reason’s attempts (or in Kant’s own stronger language – reason’s need) to move past any objects of experience. Kant also indicates in this passage that in such striving, reason, in fact, aims at cognitions that “have their reality and are by no means merely figments of the brain” (A314/B371). However, we already know that in its theoretical operation, reason’s attempts at producing such cognitions end up in an illusion (e.g., A345/B403; A350; A401-405). Then, what sort of operation of reason does Kant have in mind?

Just as one finds in Kant’s philosophy, so also in his treatment of Plato, Kant gives a wider scope of use to practical reason. In the passage immediately following his praise of Plato, Kant claims that “Plato found his ideas preeminently in everything that is practical” (A314-315/B371). By “practical” Kant means all that which “rests on freedom, which for its part stands under cognitions that are a proper product of reason” (A315/B371). The consequent elucidation of this statement shows that it is impossible to use empirical cognitions, examples, situations, and so on as the proper ground of morality. All these elements of sensible experience are subject to change, but virtue must be a constant and unchanging guide that shapes our experience and actions. Thus, virtue must aim at an unchangeable ideal or at cognitions that are the object of reason, are not in experience, and yet are not mere “figments of the brain” (A314/B371).

In his practical philosophy, Kant identifies the activity of reason that is not bounded by experience, and yet is not illusory, as being indispensable to moral actions. Not anything in experience, but reason itself must determine our will in accordance with the objectivity of the moral law. Determined in this way, one’s will acts autonomously – from within the free agent; as opposed to on the basis of the various outside determinations, which limit our agency to act morally. For Kant, “I ought never to act except in such a way that I could also will that my maxim should become a universal law” (4: 402).^[36] In other words, what I as a subject prescribe for myself as a principle of my willed action, should be universalizable – should be applicable as the same maxim for all. If it is not, then I must not act on this maxim. In order to give myself these universalizable maxims, my will must be determined by my reason. Determined in this way, the will is good and as Henry E. Allison puts it, “in the case of practical reason (or Wille) it is a matter of realizing in nature, i.e., the phenomenal world, the ends dictated by the moral law, that is, ends that are also duties. … [Notably], the duty to promote the highest good … requires the postulation of God and immortality.”^[37] However, if our reason in its theoretical activity takes the pure (a priori or pre-experiential) concepts of the understanding in order to not merely posit the regulative ideas (God, freedom, and immortality), but also to assume or try to prove the existence of some such being as “God” or “immortal soul,” then we end up with fictious cognitions.^[38]

Reason continuously seeks higher unities and thus draws on the concepts of understanding which when they are properly generated, maintain their fidelity to the world of sense; however, reason is not itself directly tied to our sensible experience but only to the concepts.^[39] Thus, in its unifying action, reason can generate ideas that have no grounding in sensible experience. In other words, reason for Kant, does not give us a “unity of possible experience” (A307/B363). The unity of reason is not discursive, but inferential. According to Kant, “reason in inferring seeks to bring the greatest manifold of cognition of the understanding to the smallest number of principles (universal conditions), and thereby to effect the highest unity of that manifold” (A305/B361). However, reason is incapable of engendering anything substantially existing. Thus, and as an Ideal of Reason, God does not exist as a being and does not generate anything.^[40] Instead, it is our reason that seeks “to determine the original being through the mere concept of the highest reality as a being that is singular, a simple, all-sufficient, eternal, etc., [and] … determine it in its unconditioned completeness through all predications” (A580/B608). However, to insist that “this reality should be given objectively, and itself constitute a thing” is to engage in construction of “a mere fiction, through which we encompass and realize the manifold of our idea in an ideal, as a particular being” (A580/B608). In other words, reason gives us an idea of an ultimately perfect being. However, if we assume that this idea corresponds to a being in existence (Dasein), we do not refer to anything meaningfully existing, but to “a mere fiction.” In this sense, too, there is an affinity between the Good in the Republic and Kant’s analysis of God – the former is beyond Being and the latter does not exist as a being, but both orient our thinking and actions. Note that “orient” does not mean “constitute,” i.e., orienting or regulative ideas can only be taken as something that reason posits, but not as something that truly exists, nor as something that can be used in order to constitute objects in experience. So, for example, in the 1786 Metaphysical Foundations of Natural Science, for Kant, Newtonian absolute space does not exist, but is rather a kind of an abstraction from the various spaces that we can think of as standing in different relations to one other. Absolute space is not a reality, but an ideality. Likewise, the “unavoidable problems of pure reason itself [which] are God, freedom and immortality” (A3/B7) acquire a regulative character in Kant, and when they do, they cease being fantastical or fictional.

Likewise, in Plato, the Good which is beyond Being, stands in the relationship to the sensible world in a manner that the Ideas that regulate our moral thinking stand to our practical actions. The look of the Good, then, has to do with the regulation of our thinking about real, practical things and not about supra-sensible and extra-mental ideas – whatever they may be. Baum indicates that Kant sees a strong affinity between his own practical philosophy and what he understands as being Plato’s.^[41] He writes, “the ἰδέα, understood as pure Ideal, did meet with Kant’s approval, since it can serve moral philosophy as a two-fold paradigm: first, like Kant’s own “Idea” (Idee), it is a product of the pure Understanding and not of empirical origin; second, it serves as the norm of moral evaluation, and as the goal of free human activity, which the latter ought to approach, even if it cannot be reached.”^[42] Kant takes Plato’s ἰδέα to be intelligible, rather than sensible. Thus, my interpretation of the ἰδέα as a “sensible look” of the Good, parts ways with Kant’s. However, two points remain: 1) both Kant and Plato articulated God and the Good, respectively, as that which does not have substantial, being-like existence (Dasein) under a concept and 2) as that which nonetheless can orient our thinking, especially, when it comes to guiding our moral actions. My interest in stressing the sensible character in Socrates’ presentation of τοῦ ἀγαθοῦ ἰδέαν (508e) lies in the fact that if we maintain this attachment to sensibility in its relation to the Good then we 1) mitigate Kant’s criticism of Plato’s untethered idealism (or metaphysical realism unmitigated by the world of sense) and 2) we bring Kant and Plato closer together on the question of the significance of the sensibility and the sensible world.

4 Conclusion

Despite or even because of his inheritance of a view of metaphysics that is merely attributed to Plato (i.e., the view that certain extra-mental entities are real and exist in some supra-sensible, otherworldly realm), Kant worked to undo the views of the dogmatic metaphysicians of his age. The epigraph to the Dreams of the Spirit-seer Illustrated by Dreams of Metaphysics (1766) speaks about the vain or empty phantasms that appear in the dreams of someone who is ill. This redoubles the idea of the title of Kant’s work. From the start, Kant concerns himself in this text with the question of what belongs to the field of mere imaginings and with the question of how that realm can be distinguished from the kind of thinking that properly belongs to philosophy. The first line of Dreams of the Spirit-seer reads, “The realm of shades is the paradise of fantastical visionaries”^[43] or in a much more economical and rather evocative German, “Das Schattenreich ist das Paradies der Phantasten.”^[44] It is shades as opposed to the light of reason and it is the invisible phantasms as opposed to that which can be examined by our understanding, assessed, and critiqued by it, that Kant sets up as contraries.

On Kant’s interpretation, a view which says that there are these entities or Ideas that exist in some supra-sensible reality and that secure the existence of all manner of beings in the empirical, sensible world is not a rigorous philosophical insight, but an illusion. This illusion belongs on the side of fantastical, but not philosophical thinking. One of the main goals of Kant’s philosophy is to reposition our understanding of metaphysics by turning it away from any such systems that attribute to Ideas the same objective, real existence that accrues to beings in the world. Specifically, Ideas cannot have a Dasein which in the categories falls under Modality and indicates that we must draw on the sensible manifold to confirm their Dasein. The sense of existence as Dasein is different from Sein – a logical possibility of existence. The latter does not yield the necessity of Dasein, but it cannot be disproven until the possibility of Dasein is established based on sensible intuition. As with the example of the concept of a two-sided figure which is a self-contradictory concept (A291/B348), if we have this “concept of straight lines and the number two” we, nonetheless, cannot derive the “proposition that with two straight lines no space at all can be enclosed” (A47/B65). Thus, Kant admits, that we are “forced to take refuge in intuition, as indeed geometry always does” (A47/B65). Sein as a logical possibility does not confirm Dasein at all. Actually or experientially, it is utterly impossible for a two-sided figure to exist. The concept of a two-sided figure has no Dasein, just as Ideas have none. There is, however, a disanalogy between this example and the Idea of God. Since the concept of a two-sided figure – and geometry in general – draws on intuition, it is provable that a two-sided figure cannot really exist. However, the Idea of God, and hence, the existential possibility or impossibility of God, cannot be proven or disproven in the same way, i.e., on the basis of violating the form of our intuition. Thus, what is left for us in the case of God is not knowledge, but belief, which undergirds the possibility of morality.^[45]

Thus, metaphysics with Kant becomes an inventory of the structures of the subjective mind, or an analysis of pure elements of cognition. Nonetheless, Kant acknowledges the propensity of reason to strive toward the ever-higher states of unity, and in this striving, to get off course. Moreover, Kant also admits that reason is inclined to outstrip the concepts of the sensible world. As I see it, this excess of reason is precisely what we witness in the interpretations of Plato (to which Kant himself adhered) that attribute to him a dualist metaphysics, metaphysical realism, or which claim that Plato insisted on a supreme power of reason and intellect over and above the senses. In my reading, Plato’s dialogues offer a nuanced view of the relationship between the sensible and the intelligible, which can only be decided in favor of the primacy of the latter at the expense of downplaying the complexity and richness of Plato’s text.

However, if we reposition our view of the sensible dimension in Plato’s thought, then we see that (1) the history of philosophy pursued a direction of interpretation of Plato that is centered on the power of reason and that (2) this direction is only a part of the way of understanding Plato. The other part lies along the lines of precisely the kind of interest that Kant expresses when he insists on the significance of sensible intuitions and sensible experience. Plato appears to have been one of Kant’s key points of departure for his articulation of the way in which the noetic and the sensible elements constitute our cognition. Furthermore, Kant’s engagement with Plato also serves as one of the roots of Kant’s critical assessment of reason and of his analysis of the realities that can and cannot be legitimately investigated or stipulated by reason. We can read Plato along the lines that bring together the sensible and the intelligible. If we do not divide the two and refrain from establishing a hierarchical relationship between them in Plato, then we also see that Kant’s own interest in limiting the extent of theoretical reason is already inscribed in Plato’s philosophy.