Today I would like to be as clear as possible within a problem which is nevertheless complicated. I have only one idea at best which I would like to develop today, and which is not only linked to the desire to help some of you in speaking about Kant in a precise way, but also to try and show a kind of development of an amazing problem throughout Kant's philosophy. The centre of everything I would like to say today is precisely this: if we stay with the Critique of Pure Reason, Kant's famous book, we can well see, in relation to the themes which concern us involving time, we can well see that there are two great operations. What these two great operations of knowledge have in common - since pure reason is concerned with knowledge - what these two great operations of knowledge have in common is that in both cases a correspondence is created, despite their heterogeneous elements, despite their difference in nature, between conceptual determinations and spatio-temporal operations.
These two great operations by which a correspondence is created - whatever the difficulties this correspondence involves given their heterogeneity - between spatio-temporal determinations and conceptual determinations are both synthetic operations. They are synthetic for very simple reasons, they are necessarily synthetic since, as we have seen, spatio-temporal determinations on the one hand and conceptual determinations on the other hand, space-time and concepts, are heterogeneous, so the act which puts them into correspondence can only be a synthesis of heterogeneities. These two synthetic operations have names. These two operations also have in common the fact of being acts of the imagination. Obviously imagination no longer means making up ideas or imagining something, since Kant gives a fundamentally new meaning to the act of imagination, since it is the act by which spatio-temporal determinations will be put into correspondence with conceptual determinations. You will ask me why he calls that "imagination"? Understand that he is already at a level where he grasps imagination at a much deeper level than in the preceding philosophies; imagination is no longer the faculty by which we produce images, it is the faculty by which we determine a space and a time in a way that conforms to a concept, but that does not flow from the concept which is of another nature than the determination of space and time. It is really the productive imagination in opposition to the reproductive imagination. When I say: I imagine my friend Pierre, this is the reproductive imagination. I could do something else besides imagine Pierre, I could say hello to him, go to his place, I could remember him, which is not the same thing as imagining him. Imagining my friend Pierre is the reproductive imagination. On the other hand, determining a space and a time in conformity to a concept, but in such a way that this determination cannot flow from the concept itself, to make a space and a time correspond to a concept, that is the act of the productive imagination. What does a mathematician or a geometer do? Or in another way, what does an artist do? They're going to make productions of space-time.
The two synthetic operations which establish the correspondences of space-time to concepts. I said that Kant gives them very strict names, and it would be very unfortunate to confuse these two operations. One is designated under the name of synthesis strictly speaking, synthesis as the act of the productive imagination and the other - which is no less synthetic - Kant saves another name for it, that of the Schema. A schema. It is also an operation of the productive imagination. One of our problems is what the difference is between a synthesis strictly speaking and a schema. We have seen what they have in common: in both cases it is a matter of determining a space and a time in correspondence with a concept. But my second problem is that if we don't stay with the Critique of Pure Reason, if we go on to one of Kant's last works, where Kant goes deeper and deeper, which is to say if we effect a confrontation with the ultimate work, the Critique of Judgement, and if we see its effect on the Critique of Pure Reason, we realise that Kant reveals to us in the Critique of Judgement an amazing double adventure: how synthesis, as act of the imagination, can be overwhelmed by a fundamental experience which is the experience of the sublime; thus that there is an operation of extreme fragility in the synthesis: something which comes from the depths [le fond] puts ???? this operation at risk at each instant, drowning it. Drowning it in a simple destruction? No, in favour no doubt of the revelation of another level which is the revelation of the sublime and thus that the synthesis of the imagination risks being overwhelmed by another act, or rather by another passion, by a sort of passion of the imagination which is the spectacle and the experience of the sublime, where the imagination vacillates on its own ground.
On the other hand, it is quite curious how it's both inspired and works in symmetry; it is really the hinge of Classicism and Romanticism. The Critique of Judgement is really the great book which all the Romantics will refer to. They had all read it, it will be determining for the whole of German Romanticism. But on the other hand as well we experience the same adventure, but under another form. The schema, which is the other act of the imagination, risks being overwhelmed by something which comes from the depths of the imagination in the same way as the synthesis, namely the experience of the sublime, the schema - [the] other act of the imagination from the point of view of knowledge - also risks being overwhelmed by something monstrous, which Kant is the first to analyse, to my knowledge. It is symbolism. In the same way that the sublime threatens at each instant to overwhelm the imagination's act of synthesis, the operation of symbolism and symbolisation threatens at each instant to overwhelm this other act of imagination which is the schema. So much so that between symbolism and the sublime, there will obviously be all sorts of echoes, as if they brought about the emergence of a sort of ground [fond] which is irreducible to knowledge, and which will testify to something else in us besides a simple faculty of knowing. Feel how beautiful it is.
So first we must go via something more reasonable, duller: what is the difference between the schema and the synthesis? The last time I tried to show what the synthesis was. The synthesis as act of the imagination consists precisely in this - but I want this to be very concrete, which is good if one is in the world and in the world there are Kantian phenomena; if you come across a typically Kantian moment in the world, then it's very good, at that moment you must speak in Kantian terms; they are phenomena which can only be grasped through Kantian spectacles, if not you pass on by. The synthesis and the schema are always the forming of a correspondence between, on the one hand conceptual determinations, and on the other spatio-temporal determinations. What defines the synthesis as distinct from the schema? The synthesis is an act of the imagination which operates here and now; there is no synthesis if it is not an operation of your imagination that you do here and now. For example, here and now, you see a diversity; or else here and now you see an organisation of space and time. You will recall that this space and this time are not yet determined: there is something in space and time. A synthesis must yet be effected which will give you a certain space and time, in such a way that you carry out a sort of isolation: if you say "that is a table", you have carried out a synthesis of space and time in conformity with a concept. There is the concept table, and then you have synthesised, you have carried out a synthesis of a certain diversity. So the principle of the synthesis is recognition, it is this. The synthesis has as its rule the process of recognition. Given this, it is obligatory that the synthesis operates here and now: look, it's a house. What does the synthesis consist in? We saw it last time: successive apprehension of parts, synthesis of apprehension, reproduction of the preceding parts in the following parts; thus the two aspects of the synthesis, apprehension and reproduction, are what I use to determine a finite space and time.
The concept is the form of the object which I qualify according to the diversity whose synthesis I have effected: it's a table, it's a house, it's a small dog.
So, in the synthesis, I have indeed effected a correspondence between a determination of space and time and a conceptual determination, the determination of space and time being carried out by the synthesis of apprehension and reproduction, and the conceptual determination referring to the form of the any-object-whatever in so far as this form of object will be determined by the diversity upon which I effect the synthesis. I would almost say that in the synthesis I go from the spatio-temporal determination to the conceptual determination and that my point of departure is here and now. You can see that, at the beginning, I only have a concept of any-object-whatever; I only have the form of an any-object-whatever which is the empty form of the concept, object = x. Why is this a concept? Because it is not at all contained in the sensible diversity. So as the form of the pure concept I have only the form of the any-object-whatever, and the synthesis of the imagination will make a spatio-temporal determination correspond to the any-object-whatever in such a way that the any-object-whatever will be specified as such or such an object: this is a house, this is a table.
There is something quite curious in Kant. When things don't work, he invents something which doesn't exist, but it doesn't matter. The schema. Put yourself in the reverse situation. You have the concept, you start from the concept. So the path of the schema will no longer be the here and now, not what your productive imagination does here and now, that is determine space and time, the schema will be on the contrary an operation that you carry out, when you carry it out, as valid at all times. "This is a house" is not valid at all times. You recall the rule of the synthesis, it's a rule of recognition. The schema: you have a concept, and the problem is to determine the spatio-temporal relation which corresponds to this concept. The synthesis is just the opposite, it's this: you carry out a spatio-temporal operation and you specify the concept according to this determination. So the operation of the synthesis, valid here and now, will correspond with, in the other direction, the determination of the schema, valid at all times. There you have a concept and you are looking for the spatio-temporal determination which is likely to correspond to it. What does that mean? When I say: the straight line is equal in all its points, Euclid's definition, I have a concept of a straight line. You will tell me, yes, but it's already spatial. Yes it's spatial, but with space, I can make a concept of space for myself. A straight line defined as a line equal in all its points doesn't yet give me any determination, and while the synthesis went from the space-time intuition to the concept carried out by a rule of recognition, the schema on the contrary will operate by a rule of production. Given a concept, how can I produce it in intuition? Which is to say in space and in time, an object conforming to the concept. Producing in space and time, that is the operation of the schema. In other words, the schema does not refer to a rule of recognition, but refers to a rule of production. The synthesis of a house is the rule of recognition according to which I say "it's a house". You say "it's a house" in front of very different things. You effect a synthesis of the given such that you relate them to the any-object-whatever "it's a house". The schema of the house is very different, it is not a rule of recognition over random diversities. The schema of the house is a rule of production, namely that you can give yourself a concept of house. For example I can take a functional definition: house = apparatus made for sheltering men, this doesn't yet give us a rule of production. The schema of the house is what allows you to produce it in experience, in space and in time, something, objects conforming to the concept. But that definition does not get out of the concept; you can turn the concept around all you like in all directions, apparatus made for sheltering men, you will not draw rules of production from it, the rules of construction of the house. If you have the rule of production you have a schema. It is very interesting from the point of view of a study of judgement. Consider the two following judgements: the straight line is a line equal in all its points; there you have a logical or conceptual definition, you have the concept of the straight line. If you say "the straight line is black", you have an encounter in experience, not all straight lines are black. The straight line is the shortest path from one point to another, it's a type of judgement, a quite extraordinary one according to Kant, and why? Because it cannot be reduced to either of the two extremes that we have just seen. What is the shortest path? Kant tells us that the shortest path is the rule of production of a line qua straight. If you want to obtain a straight line, you take the shortest path. It is not a predicate at all. When you say: the straight line is the shortest path, you seem to treat the shortest path like an attribute or a predicate, when in fact it is not a predicate at all, it's a rule of production. The shortest path is the rule of production of a line qua straight line in space and in time.
Why in time? Here you must understand why time is involved in this, and even more deeply still than space. You can't define the shortest independently of time. How is it a rule of production? If someone says to you: you want to draw a straight line, very well, take the shortest! We no longer understand the judgement; we say so many things without knowing that we say them. Once again it is true historically that the judgement "the straight line is the shortest path between one point and another" has very very precise implications from a geometrical point of view, namely that while the Euclidean or conceptual definition of the straight line is indeed a line equal in all its points, the straight line as the shortest path from one point to another is an Archimedean notion, and Archimedean geometry has quite different principles than Euclidean geometry. The notion "the straight line is the shortest path" is purely nonsensical if you separate it from a whole calculus which is a comparison of heterogeneous elements. Here you find the theme of the synthesis again. The heterogeneous elements are not the different sorts of lines, straight or not straight, it's the confrontation of the curve and the straight line. It's the Archimedean theme of the minimal angle, of the smallest angle which is formed by the tangent and the curve. The shortest path is a notion which is inseparable from the calculus which in antiquity was called the calculus of exhaustion in which the straight line and the curve are treated in a synthetic confrontation. Given this, tracing the tangent to the curve is indeed a rule of production. So it is in this sense that I can say, despite appearances, that the straight line is the shortest path, we must see that the shortest path is not an attribute of the line and this is not surprising since "the shortest" is a relation. A relation is not an attribute. If I say Pierre is smaller than Paul, "smaller" is not an attribute of Pierre. Even Plato said that if Pierre is smaller than Paul, he is bigger than Jean. A relation is not an attribute. "The shortest" is the rule according to which I produce a line qua straight line in space and in time. In other words, I make a correspondence between a conceptual determination, that is the straight line defined as equal in all its points, and a spatio-temporal determination by which I can produce as many straight lines as I like in experience.
In one of Kant's distant successors, namely Husserl, there is something like this which also interests me very much, but I think Husserl has let something slip away. Husserl said to us: take two ends, at the two extremities of the chain, you have pure essences. For example the circle, as pure geometrical essence. And then, at the other end, you have things in experience which correspond to the circle. I can make an open-ended list of them: a plate, a wheel of a car, the sun. I would say, in technical terms, that all of these things in experience, a wheel, the sun, a plate, are subsumed under the concept of a circle. Can you not see a series of intermediaries between these two extremes, which will be of great importance from Kant onwards. But notions, they must be lived, the abstract is lived, it's really the same. At the moment when something becomes very very abstract, then you can say that it concerns something lived. We already know that "between the two" is not a mixture, that it will be a zone discovered by Kant. Take a word: "the ring" [le rond]. I can always say that the circle is a ring. The conceptual determination of the circle is: where points are situated at equal distance from a common point named centre. That's the conceptual determination, the empirical determination or determinations are the plate, the wheel and the sun. When I say: "oh what a beautiful ring [rond] !" - I was saying just before that the two extremes are the line conceptually defined as equal in all its points, and then "the straight line is black" which is an encounter in experience, a case of a straight line. But between the two, as a perfectly specific region, there is "the straight line is the shortest path."
Now between the circle and the illustrations of the circle in experience, I would almost say the images of the circle : the plate is an image of a circle, the wheel is an image of a circle, but I have this bizarre thing: a ring [rond]! It is very curious to do the logical analysis of a ring. I would say the same thing: if we go far enough in our analysis of the round, we will see that it's a rule of production; for example a round is the circumference [le tour], no, the round is what allows us to make a circumference.
The circumference is what allows us to make certain materials round. The ring must obviously be lived dynamically, as a dynamic process; in the same way that "the straight line is the shortest path" implies an operation by which the length of a curve is compared to that of a straight line, which is to say by which there is a linearisation of the curve, the ring implies an operation by which something in experience is rounded. It's a process of production of the circumference-type which allows the production in experience of things corresponding to the concept circle.
Where Husserl is obviously wrong is when he discovers this sphere of the ring - we have just shown how the ring is completely in the same domain as the shortest, it's the same domain of being - Husserl is wrong because he makes them into inexact essences, like subordinate essences. The direction that Kant went in seems much stronger to me, making them precisely into acts of the productive imagination. Here you can see in what respect the productive imagination is more profound than the reproductive imagination. The reproductive imagination is when you can imagine circles, concrete circles; you can imagine a circle drawn on a blackboard with red chalk, you can imagine a plate... all that is the reproductive imagination. But the circumference that allows you to make rounds, which allows you to round things, which is to say to produce in experience something conforming to the concept of circle, that doesn't depend on the concept of circle, that doesn't flow from the concept of circle, it's a schema, and that is the act of productive imagination.
You can see why Kant feels the need to discover a domain of the productive imagination distinct from the simply empirical or reproductive imagination. You can see the difference between a schema and a synthesis, if you have understood that I have finished with my first point: what the difference was between the two fundamental acts, within the context of knowledge: the schematism and the synthesis.
The schematism is not a case of reflective judgement, it is a dimension of determining judgement. I will do the story of reflective judgement on request.
The a posteriori is what is in space and in time. It's the plate, the wheel, the sun. A rule of production is solely a determination of space or of time conforming to the concept. Take another case. You make yourself a concept of a lion; you can define it by genus and specific difference. You can define it in this way: big animal, mammal, with a mane, growling. You make a concept. You can also make yourself lion images: a small lion, a big lion, a desert lion, a mountain lion; you have your lion images. What would the schema of a lion be? I would say in this case, not in all cases, that the concept is the determination of the species, or its the determination by genus and specific differences. The image in experience is all the individuals of this species, the schema of the lion is something which is neither the examples of a lion... [end of tape] ... there are spatio-temporal rhythms, spatio-temporal attitudes [allures]. We speak both of an animal's territory and an animal's domain, with its paths, with the traces that it leaves in its domain, with the times that it uses a particular path, all that is a spatio-temporal dynamism that you will not draw from the concept. I am not going to draw from the concept of a lion the way it inhabits space and time. From one tooth you can draw something of a mode of living: this is a carnivore. But really the spatio-temporal dynamism of an animal, that is really - I can't say its rule of production - but it's something productive, it's the way in which it produces a spatio-temporal domain in experience in conformity with its own concept. The lion is Kantian, all the animals are Kantian. What is the schema of the spider? The schema of the spider is its web, and its web is the way it occupies space and time. The proof is that the concept of the spider, I don't know how, but you can take the concept of a spider; the concept of a spider will include all of its anatomical parts and even the physiological functions of the spider. Thus one will encounter that funny sort of organ with which the spider makes his web. But can you deduce from it what we can now call the spatio-temporal being, and the correspondence of the web with the concept of a spider, which is to say with the spider as organism. It's very curious because it varies enormously according to the species of spider. There are cases of very extraordinary spiders which, when you mutilate one of their legs, which is nevertheless not used for fabrication, make abnormal webs in relation to their own species, they make a pathological web. What happened? As if a disturbance in space and time corresponded to the mutilation. I would say that the schema of an animal is its spatio-temporal dynamism.
Where Kant was determining, after Husserl, there were all sorts of experiments and I'm thinking of a funny sort of school which, at one time, had some success. It was the psychologists of the WŸrzburg school, they were closely linked to a Kantian lineage. They carried out psychological experiments. They said that there are three sorts of things: there's thought which operates with concepts, and then there's perception which grasps things, and if need be there is the imagination which reproduces things: but they said that there is also another dimension which they gave a very curious name to. They spoke of the direction of consciousness, or even of the intention of consciousness, or even of an empty intention. What is an empty intention? I think of a lion and an image of a lion comes to me; I think of a rhinoceros and I can see the rhinoceros very well in the image which comes to my mind, that is an intention. I have a conscious intention and an image comes to fill it, the image of the rhinoceros. So they carried out experiments on this, it was experimental psychology. They set the rules of the game, you're going to laugh: you stop yourself from having an image, you are given a word and you take a view which both excludes any image, and which nevertheless is not purely conceptual; what does that produce? It produces sorts of conscious orientations, i.e. spatio-temporal directions. The more abstract it was, the better. It was in order to persuade us that there were three possible attitudes of conscious: abstract thinking consciousness, for example proletariat, where one had to work for the proletariat. First reaction: proletariat = the class defined by... etc... I would say that that is the conceptual definition of the proletariat; it is a certain attitude of consciousness towards a word: I aim at the concept through the word. Second attitude of consciousness: through the word proletariat I evoke one, a proletarian: "ah yes, I've seen one!" That is really the empirical attitude, an image. Sartre, in his book The Psychology of Imagination, describes the third attitude, that of the WŸrzburg-type experiments, and he gives descriptions of people's responses; I see a sort of black wave advancing; it defined a sort of rhythm. Managing to grasp an attitude of consciousness, a sort of way of occupying space and time: the proletariat doesn't fill space and time in the same way as the bourgeoisie. At that moment you have the schema. Or else another method was to take a word that is empty for you, whose meaning you don't know: in a precious poem, and you carry out the direction of consciousness, you don't make an association, but a vague direction of consciousness, a sort of purely lived spatio-temporal opening. How does a consciousness orient itself following the sound of an understood word? There you have a whole dimension of spatio-temporal dynamisms which are somewhat similar to the schema. The schemas are subdivided, but while the concepts are subdivided according to genus and species, the schema will have another mode of division. In fact when I said that the true schema of the circle was the circumference, it is in fact a sub-schema because the circumference already implies certain modes, the circumference is the rule of production in order to obtain things in experience, but in these conditions of suitable materials. In other cases, something else would be required. I don't know how bicycle wheels are made? When phenomenology and then Heidegger, then all sorts of psychiatrists go on to define ways of being in space and in time, complexes or blocks of space-time, rhythmic blocks, I'd say that all that derives from Kant. Indeed the ethnologist constructs schemata of men to the extent that he describes manners: a civilisation defines itself, amongst other ways, by a block of space-time, by certain spatio-temporal rhythms which will vary the concept of man. It's obvious that an African, an American or an Indian won't inhabit space and time in the same way. What is interesting is when, in a limited space, we see the coexistence of different types of space-times. I could equally say that an artist operates through blocks of space-time. An artist is above all a rhythmicist. What is a rhythm? It's a block of space-time, it's a spatio-temporal block. But each time you have a concept, you don't yet have the rhythmicity of the things which are subordinated to it. A concept, at best, will give you the beat or the tempo. Which is to say a homogeneous beat, but rhythmicity is something entirely different from a homogeneous beat, something entirely different from a tempo.
I'll go on to my second point. You remember that we saw, in relation to the synthesis, this adventure of the sublime. Kant realises that the synthesis of the imagination, such as it arises in knowledge, rests on a basis of a different nature, namely that the synthesis of the imagination in all its aspects assumes an aesthetic comprehension, an aesthetic comprehension both of the thing to be measured and the unit of measure. You must be clear that aesthetic comprehension is not part of the synthesis, it's the basis [sol] that the synthesis rests on. I would say that it is not the ground [fondement] of the synthesis but that it is the foundation [fondation] of synthesis. At the same time that he discovers this basis, he discovers the extraordinary viability of this basis. He doesn't discover this basis without also seeing that this basis is ????? Why? Because what the synthesis rests on is fundamentally fragile, because the aesthetic comprehension of the unit of measure, assumed by all effective measurement, can at each instant be overwhelmed, which is to say that between the synthesis and its basis there is the constant risk of the emergence of a sort of thrust coming up from underground [sous-sol], and this underground will break the synthesis. For the synthesis rests on the aesthetic comprehension of the unit of measure, an aesthetic comprehension which is irreducible to the operations of knowledge. Why is this very fragile? Because at every instant there are types of phenomena in space and in time which risk overturning the aesthetic comprehension of the unit of measure, and it's the sublime, where the imagination finds itself before its limit. It is confronted with its own limit, it can no longer be at the service of the concepts of the understanding. To be at the service of the concepts of the understanding is to determine space and time in conformity with the concepts of the understanding, and here it can no longer do this: the imagination finds itself blocked before its own limit: the immense ocean, the infinite heavens, all that overturns it, it discovers its own impotence, it starts to stutter. And it is thus at the same time that the basis of the synthesis, namely aesthetic comprehension, and the underground of the synthesis, namely the sublime in so far as it overturns the base, is discovered. But there's a consolation; at the moment that the imagination finds that it is impotent, no longer able to serve the understanding, it makes us discover in ourselves a still more beautiful faculty which is like the faculty of the infinite. So much so that at the moment we feel for our imagination and suffer with it, since it has become impotent, a new faculty is awakened in us, the faculty of the supersensible.
When the storm is over, when the avalanche is finished, I rediscover my syntheses, but for a moment the horizon of knowledge will have been traversed by something which came from elsewhere, it was the eruption of the sublime which is not an object of knowledge. We must put ourselves in Kant's place, assuming that he has discovered all of this. He says to himself that there must be something analogous for the schema. The schema is also an operation of knowledge, we saw its relation to the synthesis; the schema must also follow its own limit and have something overwhelm it. It must be something different, a different adventure. There is no reason to treat philosophy in a different way from art or science. There are differences but they aren't at the level we think they are. Here is the schema of the schema: I make a big white ring [rond] up top and I put A on the side. To explain: this big white ring called A is the concept of a. Concept of a. Vertically, I make a dotted line, above all dotted, with an arrow at the end, and at the end of the arrow, beneath, I put a. I'll explain, but for those who want the complete schema: from the a which is beneath the end of my arrow, I make a filled line this time, a spray of little arrows, and under each of the little arrows I put a', a'', a '''. The big A is the concept a, at the end of my dotted arrow I have a, it's the schema of A, that is, the spatio-temporal determination A. If I take an example: A = concept of the circle, a = the ring or the schema of the circle, which is to say the rule of production. Then a', a'', a''' are the empirical things which conform to the schema, and led back to the concept by the schema. So a' = plate, a'' = wheel, a''' = sun, in our previous example. Why is it that the arrow which goes from the concept to the schema was dotted? Precisely in order to indicate subtly that the symbol which he opposes [to] or which he explicitly distinguishes from the schema in the Critique of Judgement, and it's among the most admirable pages in Kant. Well that's going to complicate things and here are the two schemas.
A = concept. a = schema of the concept, which is to say spatio-temporal determinations. B, dotted arrow and b. We need that to make a schema. I'll give examples. First example: A = the sun. a = to rise (spatio-temporal determination). Let's say that this is the auto-schema of the concept. B, the virtue of the concept, b: schema or intuition = x?
Second example: A = the sun, a = to set. You can see that these are two sub-schemas, I could have taken rising and setting in a single schema. B = death. b = intuition = x of death. Third example: A = a mill. a = a type of mill which implies a certain space-time, which is to say not the general schema of a mill, but a certain schema corresponding to category of mills = hand-mill. B = despotic constitution. b: intuition = ? = x.
I have two remarks to make if you understand these examples. There would be symbolisation when you use the schema or intuition a, not in relation to the corresponding concept A, but in relation to the quite different concept B for which you have no intuition of a schema. At that moment the schema ceases to be a rule of production in relation to its concept, and becomes a rule of reflection in relation to the other concept. So much so that you have the Kantian sequence: the synthesis refers to a rule of recognition, the schema refers to rules of production, the symbol refers to rules of reflection.
Why don't I have any intuition corresponding to the concept? Two possible cases: either because I don't in fact have one, because I lack the necessary knowledge, but I could have it, I could form a schema of the concept. Or else by virtue of the special nature of this concept.