I would like to finish these meetings on Leibniz by presenting the problem that I wanted to consider. I return to this question that I asked from the start, specifically: what does this image mean that good sense often creates about philosophy, what does this image mean that good sense sometimes produces about philosophy, like a kind of locus of discussion in which philosophers are fundamentally not in agreement? A kind of philosophical atmosphere in which people dispute, fight among themselves, whereas at least in science, they know what they are talking about. We are told as well that all philosophers say the same thing, they all agree or all hold opposite views. It’s in relation to Leibniz that I would like to select some very precise examples. What does it mean that two philosophies do not agree? Polemics, like a certain state of things that traverses certain disciplines, I do not find that there are more polemics in philosophy than there are in science or in art. What is a philosopher who critiques another philosopher? What is the function of critique? Leibniz offers us this example: what does the opposition between Kant and Leibniz mean, once we have said that it was a fundamental opposition in the history of philosophy? What does it mean for Kant to undertake a critique of Leibniz? I would like to number what I want to tell you. An initial task: to localize the oppositions. There are two fundamental oppositions from the point of view of knowledge. They function like thesis and antithesis. When we manage to trace the great philosophical oppositions, on the level of the concepts used by one philosopher or another, we also have to evaluate their relations to these oppositions. They [the oppositions] are not of equal value. Perhaps one does happen to have greater weight than another, to be more decisive. If you fail to organize the oppositions, I think that you are no longer able to understand what the subject is in a polemic.

First opposition between Leibniz and Kant, from the point of view of knowledge. I will let Leibniz speak. A Leibnizian proposition: all propositions are analytical, and knowledge can proceed only by analytical propositions. You recall that we call “analytical proposition” a proposition in which one of the two terms of the proposition is contained in the concept of the other. It’s a philosophical formula. We can already sense that there is no point in arguing at this level. Why? Because there is already something implied, specifically that there is a certain model of knowledge. What is presupposed, but in science as well, there are also presuppositions; what is presupposed is a certain ideal of knowledge, specifically knowing is discovering what is included in the concept. It’s a definition of knowledge. We are pleased to have a definition of knowledge, but why this one rather that something else?
From the other side, Kant arises and says: there are synthetic propositions. You see what a synthetic proposition is: it’s a proposition in which one of the terms is not contained in the concept of the other. Is this a cry? Is this a proposition? Against Leibniz, he says, “no”; he says that there are synthetic propositions and that knowledge exists only through synthetic propositions. The opposition seems perfect. At this point, a thousand questions assail me: What would that mean to argue, to argue about who is right, who is right about what? Is this provable, are we in the domain of decidable propositions? I say simply that the Kantian definition must interest you because, if you consider it closely, it also implies a certain conception of knowledge, and it happens that this conception of knowledge is very different from Leibniz’s. When one says that knowledge proceeds only through synthetic propositions, that is, a proposition such that one of its terms is not contained in the concept of the other, there is therefore a synthesis between the two terms. Someone who says this can no longer base knowledge on the Leibnizian conception.
He will tell us, on the contrary, that to know is not at all to discover what is included in a concept, that knowledge necessarily means leaving behind one concept in order to affirm something else. We call “synthesis” the act through which one leaves a concept behind in order to attribute to it or to affirm something else. In other words, to know is always to go beyond the concept. Knowing is to go beyond [connaître c’est dépasser]. Understand all that is in play here. In the first conception, to know is to have a concept and discover what is contained in the concept. I would say about that knowledge that it is based on a particular model which is one of passion or of perception. To know is finally to perceive something, to know is to apprehend, a passive model of knowledge, even if many activities depend on it. In the other case, to the contrary, it means leaving the concept behind in order to affirm something, and is a model of the knowledge-act [un modèle de la connaissance acte].

I return to my two propositions. Let us suppose that we are referees. We find ourselves faced with these two propositions, and we say: what do I choose? First when I say: is it decidable? What would that mean? It could mean that it’s a question of fact. One has to find the facts that allow one to say that one or the other is right. Obviously, it’s not that. Philosophical propositions, to some extent, aren’t justifiable on the basis of a verification of facts. That is why philosophy has always distinguished two questions, and Kant especially will take this distinction up again. This distinction was formulated in Latin: quid facti, what is derived from fact [qu'en est-il du fait], and quid juris, what is derived from principle [qu'en est-il du droit]. And if philosophy is concerned with principle, it is precisely because it poses questions that are called de jure questions [questions de droit]. What does it mean that my two paradoxical propositions, Leibniz’s and Kant’s, are not justifiable on the basis of a factual response? It means that in fact, there is no problem because all the time we encounter phenomena that are synthetic phenomena. Indeed, in my simplest judgments, I pass my time operating syntheses. I say, for example, that this straight line is white.

It is quite obvious that with this, I am affirming about a straight line something that is not contained in the concept of straight line. Why? Every straight line is not white. That this straight line is white is obviously an encounter in experience; I could not have made such a statement beforehand. I therefore encounter in experience straight lines that are white. It’s a synthesis, and we call this kind of synthesis *a posteriori*, that is, given in experience. Thus, there are syntheses of fact, but that does not resolve the problem. Why? For a very simple reason: this straight line [that] is white does not constitute knowledge. It’s a protocol of experience. Knowledge is something other than tracing protocols of experience.
When does one know? One knows when a proposition appeals to a principle [se réclame d’un droit]. What defines a proposition’s principle is the universal and the necessary. When I say that a straight line is the shortest path from one point to another, I maintain a proposition in principle (une proposition de droit). Why? Because I don’t need to measure each straight line to know that, if it’s straight, it’s the shortest path. Every straight line, beforehand, a priori, that is, independently of experience, is the shortest path from one point to another, otherwise it would not be a straight line. Thus, I would say that the proposition “a straight line is the shortest path” constitutes indeed a proposition of knowledge. I do not await experience to discover that a straight line is the shortest path; to the contrary, I determine the experience since the shortest path from one point to another is my way of tracing a straight line experientially. Any straight line is necessarily the shortest path from one point to another. This is a proposition of knowledge and not a protocol proposition. Let us take this proposition, it’s an a priori proposition. In this, are we going to be able finally to pose the question of separation between Leibniz and Kant, specifically is it an analytical proposition or is it a synthetic proposition?

Kant says something very simple: it’s necessarily, a priori, a synthetic proposition. Why? Because when you say that the straight line is the shortest path from one point to another, you are leaving behind the concept “straight line.” Isn’t it the content in a straight line to be the shortest path from one point to another? It goes without saying that Leibniz would say that it is the content in “straight line.” Kant says no, the concept “straight line”, according to the Euclidian definition is: line ex aequo in all of its points. You won’t draw from this the shortest path between one point and another. You have to leave the concept behind to affirm something else about it. We’re not convinced. Why does Kant say that? Kant would answer, I suppose, that the shortest path to another is a concept that implies a comparison, the comparison of the shortest line with other lines that are either broken lines or curvilinear lines, that is, curves. I cannot say that the straight line is the shortest path from one point to another without implying a comparison, the relation of the straight line to curved lines. For Kant this suffices to say that a synthesis lies therein; you are forced to leave the “straight line” concept in order to reach the “curved line” concept, and it’s in the relation of straight lines to curved lines that you say the straight line is the shortest path from one point to another. . . It’s a synthesis, thus knowledge is a synthetic operation. Would Leibniz be disturbed by that? No, he would say that obviously you have to keep in mind the “curved line” concept when you say that the straight line is the shortest path from one point to another, but Leibniz is the creator of a differential calculus through which the straight line is going to be considered as the limit of curves. There is a process to the limit. Hence Leibniz’s theme: it’s an analytical relation, only it’s an infinite analysis. The straight line is the limit of the curve, just as rest is the limit of movement. Does this advance us? So either one can no longer resolve this, or they mean the same thing. [If] they say the same thing, what would this be? It would mean that what Leibniz calls infinite analysis is the same thing as what Kant calls finite synthesis. Henceforth, it’s only a question of words. In this perspective, at that point, we would say that they agree in order to establish a difference in nature, one of them between finite analysis and infinite analysis, the other between analysis and synthesis. It comes down to the same thing: what Leibniz calls infinite analysis, Kant will call finite synthesis.

You see the good sense idea that, simultaneously, a philosophical dispute is inextricable since we cannot decide who is right, and at the same time, knowing who is right is without any importance since they both say the same thing. Good sense can conclude just as well: the only good philosophy is me. Tragic situation. Because if good sense achieves the goals of philosophy, better than philosophy itself does it, then there is no reason to wear yourself out doing philosophy. So?
Let’s look for a kind of bifurcation since this first great opposition between Leibniz and Kant, even if it now seems obvious too us, isn’t this because, in fact, this opposition moves well beyond itself toward a deeper opposition, and if we don’t see the deeper opposition, we can understand nothing. What would this second, deeper opposition be?
We saw that there was a great Leibnizian proposition, called the principle of indiscernibles, notably that any difference, in the final instance, is conceptual. Any difference is in the concept. If two things differ, they cannot simply differ by number, by figure, by movement, but rather their concept must not be the same. Every difference is conceptual. See how this proposition is truly the presupposition of Leibniz’s preceding proposition. If he is right on this point, if every difference is conceptual, it is quite obvious that it’s by analyzing concepts that we know, since knowing is knowing through differences. Thus, if every difference, in the final instance, is conceptual, the analysis of the concept will make us know the difference, and will therefore cause us quite simply to know. We see into which quite advanced mathematical task this drew Leibniz, [a task] which consisted in showing the differences between figures, the differences between numbers, referring to differences in the concepts. Ok, what is Kant’s proposition in opposition to the second Leibnizian proposition? Here again, this is going to be pretty odd [un drôle de truc]. Kant maintains a very strange proposition: if you look closely at the world presented to you, you will see that it is composed of two sorts of irreducible determinations: you have conceptual determinations that always correspond to what a thing is, I can even say that a concept is the representation of what the thing is. You have determinations of this sort, for example, the lion is an animal that roars; that’s a conceptual determination. And then you have another kind of determination altogether. Kant proposes his great thing [son grand truc]: he says that it’s no longer conceptual determinations, but spatio-temporal determinations. What are these spatio-temporal determinations? It’s the fact that the thing is here and now, that it is to the right or to the left, that it occupies one kind of space or another, that it describes a space, that it lasts a certain time. And so, however far you push the analysis of concepts, you will never arrive at this domain of spatio-temporal determinations by analyzing concepts. Although you might push your analysis of the concept to infinity, you will never find a determination in the concept that takes this into account for you: that this thing is on the right or on the left.

What does he mean? He selects examples for himself that initially seem very convincing. Consider two hands. Everyone knows that two hands don’t have exactly the same traits, nor the same distribution of pores. In fact, there are no two hands that are identical. And this is a point for Leibniz: if there are two things, they must differ through the concept, it’s his principle of indiscernibles.
Kant says that, in fact, it is indeed possible, but that’s not important. He says that it’s without interest. Discussions never pass through the true and the false, they pass through: does it have any interest whatsoever, or is it a platitude? A madman is not a question of fact, he’s also a question quid juris. It’s not someone who says things that are false. There are loads of mathematicians who completely invent absolutely crazy theories. Why are they crazy? Because they are false or contradictory? No, they are determined by the fact that they manipulate an enormous conceptual and mathematical apparatus [appareillage], for example, for propositions stripped of all interest.
Kant would dare to tell Leibniz that what you are saying about the two hands with their different skin features [différences de pores] has no interest since you can conceive quid juris, in principle but not in fact, you can conceive of two hands belonging to the same person, having exactly the same distribution of pores, the same outline of traits. This is not logically contradictory, even if it does not exist in fact. But, says Kant, there is something nonetheless that is very odd: however far you push your analysis, these two hands are identical, but admire the fact that they cannot be superposed. You have your two absolutely identical hands, you cut them in order to have a radical degree of mobility. You cannot cause them to coincide; you cannot superpose them. Why? You cannot superpose them, says Kant, because there is a right and a left. They can be absolutely identical in everything else, there is still one that is the right hand and the other the left hand. That means that there is a spatial determination irreducible to the order of the concept. The concept of your two hands can be strictly identical, however far you push the analysis, there will still be one of them that is my right hand and one that is my left hand. You cannot cause them to be superposed. Under what condition can you cause two figures to be superposed? On the condition of having access to a dimension supplementary to that of the figures . . . It’s because there is a third dimension of space that you can cause two flat figures to be superposed. You could cause two volumes to be superposed if you have access to a fourth dimension. There is an irreducibility in the order of space. The same thing holds for time: there is an irreducibility in the order of time. Thus, however far you push the analysis of conceptual differences, an order of difference will always remain outside of the concepts and the conceptual differences. This will be spatio-temporal differences.

Does Kant again gain the stronger position? Let’s go back to the straight line. [Regarding] the idea of synthesis, we are going to recognize that it was not a matter of mere words for Leibniz. If we stopped at the analysis-synthesis difference, we didn’t have the means of finding [more]. We are in the process of discovering the extent to which this is something more than a matter of words. Kant is saying: as far as you go in your analysis, you will have an irreducible order of time and space, irreducible to the order of the concept. In other words, space and time are not concepts. There are two sorts of determinations: determinations of concepts and spatio-temporal determinations. What does Kant mean when he says that the straight line is the shortest path from one point to another, that it’s a synthetic proposition? What he means is this: [the] straight line is indeed a conceptual determination, but the shortest path from one point to another is not a conceptual determination, but a spatio-temporal determination. The two are irreducible. You will never be able to deduce one from the other. There is a synthesis between them.
And what is knowing? Knowing is creating the synthesis of conceptual determinations and spatio-temporal determinations. And so he is in the process of tearing space and time from the concept, from the logical concept. Is it by chance that he himself will name this operation Aesthetics? Even on the most vulgar level of aesthetics, the best known word – the theory of art --, won’t this liberation of space and time in relation to logical concepts be the basis of any discipline called aesthetics?
You see now how it is that, at this second level, Kant would define synthesis. He would say that synthesis is the act through which I leave behind all concepts in order to affirm something irreducible to concepts. Knowing is creating a synthesis because it necessarily means leaving behind all concepts in order to affirm something extra-conceptual in it. The straight line, concept, I leave it behind, it’s the shortest path from one point to another, a spatio-temporal, extra-conceptual determination. What is the difference between this second Kantian proposition and the first? Just admire the progress Kant made. Kant’s first definition – when he was saying that knowing means operating through synthesis – this is issuing synthetic propositions, Kant’s first proposition amounted to this: knowing means leaving behind a concept in order to affirm about it something that was not contained in it. But at this level, I could not know if he was right. Leibniz arrived and said that, in the name of an infinite analysis, what I affirm about a concept will always be contained in the concept. A second, deeper level: Kant no longer tells us that knowing means leaving a concept behind in order to affirm something that would be like another concept. Rather [he says that] knowing means leaving one concept in order to leave behind all concepts, and to affirm something about it that is irreducible to the order of the concept in general. This is a much more interesting proposition.

Yet again, they react [on rebondit]. Is this decidable? One of them tells us that every difference is conceptual in the last instance, and therefore you can affirm nothing about a concept that might go outside the order of the concept in general; the other one tells us that there are two kinds of differences, conceptual differences and spatio-temporal differences such that knowing necessarily means leaving behind the concept in order to affirm something about it that is irreducible to all concepts in general, specifically something that concerns space and time.
At this point, we realize that we haven’t left all that behind because we realize that Kant, quietly – and he wasn’t obligated to say it, even since he could say it a hundred pages later – Kant can only maintain the proposition he just suggested about the irreducibility of spatio-temporal determinations in relation to conceptual determination, he can only affirm this irreducibility because he dealt a master stroke [coup de force]. For his proposition to make sense, he had to change radically the traditional definition of space and time. I hope that you are becoming more sensitive [to this]. He gives a completely innovative determination of space and time. What does that mean?
We arrive at a third level of the Kant-Leibniz opposition. This opposition is stripped of any interest if we do not see that the Leibnizian propositions and the Kantian propositions are distributed in two completely different space-times. In other words, it’s not even the same space-time about which Leibniz said: all of these determinations of space and time are reducible to conceptual determinations; and this other one about which Kant told us that the determinations [of space-time] are absolutely irreducible to the order of the concept. This is what we have to show in a simple way; take note that this is a moment in which thought reels. For a very, very long time, space was defined as, to some extent, the order of coexistences, or the order of simultaneities. And time was defined as the order of successions. So, is it by chance that Leibniz is the one who pushes this very ancient conception to its limit, all the way to a kind of absolute formulation? Leibniz adds and states it formally: space is the order of possible coexistences and time is the order of possible successions. By adding “possible,” why does he push this to the absolute? Because it refers to his theory of compossibility and of the world. Thus, he captures in this way the old conception of space and time, and he uses it for his own system. At first glance, that seems rather good. In fact, it’s always delicate when someone tells me: define space, define time; if I don’t say by reflex that space is the order of successions and space is the order of coexistences, at least that’s something [c’est quand même un petit quelque chose]. What bothers Kant can be found in his most beautiful pages. He says: but not at all. Kant says that this just won’t do, he says that, on the one hand, I cannot define space as the order of coexistences, on the other hand, I cannot define time as the order of successions. Why? Because “coexistences,” after all, belong to time. Coexistence means, literally, at the same time. In other words, it’s a modality of time. Time is a form in which occur not only that which succeeds something, but also that which is at the same time. In other words, coexistence or simultaneity is a modality of time. At some far distant date when there will be a famous theory called the theory of simultaneity, of which one of the fundamental aspects will be to think simultaneity in terms of time, I don’t at all say that Kant invented relativity, but that such a formula, particularly what we already found comprehensible in it, would not have had this comprehensible element if Kant hadn’t been there centuries before. Kant is the first one to tell us that simultaneity does not belong to space, but belongs to time.

This is already a revolution in the order of concepts. In other words, Kant will say that time has three modalities: what lasts through it is called permanence; what follows after something else within it is called succession; and what coexists within it is called simultaneity of coexistence. I cannot define time through the order of successions since succession is only a modality of time, and I have no reason to privilege this modality over the others. And another conclusion at the same time: I cannot define space through the order of coexistences since coexistence does not belong to space. If Kant had maintained the classical definition of time and space, order of coexistences and of successions, he couldn’t have, or at least there wouldn’t have been any interest in doing so, he couldn’t have criticized Leibniz since if I define space through the order of coexistences and time through the order of successions, it goes without saying, whereas space and time refer in the last instance to that which follows something else and to that which coexists, that is, to something that one can enunciate within the order of the concept. There is no longer any difference between spatio-temporal differences and conceptual differences. In fact, the order of successions receives its raison d’être from that which follows, the order of coexistences receives it raison d’être from that which coexists. At that point, it’s conceptual difference that is the last word, on all differences. Kant couldn’t break with classical concepts, pushed to the absolute by Leibniz, if he didn’t propose to us another conception of space and time. This conception is the most unusual and the most familiar. What is space? Space is a form. That means that it’s not a substance and that it does not refer to substances. When I say that space is the order of possible coexistences, the order of possible coexistences is clarified in the last instance by things that coexist. In other words, the spatial order must find its reason in the order of things that fill space. When Kant says that space is a form, that is, is not a substance, that means that it does not refer to things that fill it. It’s a form, and how must we define it? He tells us that it’s the form of exteriority. It’s the form through which everything that is exterior to us reaches us, OK, but that’s not all it is; it’s also the form through which everything that is exterior to itself occurs. In this, he can again jump back into tradition. Tradition had always defined space as partes extra partes, one part of space is exterior to another part. But here we find that Kant takes what was only a characteristic of space in order to make it the essence of space. Space is the form of exteriority, that is the form through which what is exterior to us reaches us, and through which what remains exterior to itself occurs. If there were no space, there would be no exteriority.

Let’s jump to time. Kant is going to provide the symmetrical definition, he hits us with time as form of interiority. What does that mean? First, that time is the form of that which happens to us as interior, interior to ourselves. But it does not mean only that. Things are in time, which implies that they have an interiority. Time is the way in which the thing is interior to itself.
If we jump and if we make some connections [rapprochements], much later there will be philosophies of time, and much later time will become the principal problem of philosophy. For a long time, things were not like that. If you take classical philosophy, certainly there are philosophies greatly interested in the problem of time, and they appeared unusual. Why are the so-called “unforgettable” pages on time by Saint Augustine always shown to us? The principal problem of classical philosophy is the problem of extension [étendue], and notably what the relation is between thought and extension, once it is said that thought is not part of extension.
And it is well known that so-called classical philosophy attaches a great importance to the corresponding problem, the union of thought and extension, in the particular relation of the union of soul and body. It is therefore the relation of thought to that which appears most opaque to thought, specifically extension [l’étendue]. In some ways, some people find the source of modern philosophy in a kind of change of problematic, in which thought commences to confront time and no longer extension. The problem of the relationship between thought and time has never ceased to cause difficulties for philosophy, as if the real thing that philosophy confronted was the form of time and not the form of space. Kant created this kind of revolution: he ripped space and time from the order of the concept because he gave two absolutely new determinations of space and time: the form of exteriority and the form of interiority. Leibniz is the end of the seventeenth century, start of the eighteenth, while Kant is the eighteenth century. There is not much time between them. So what happened? We must see how everything intervenes: scientific mutations, so-called Newtonian science, political events. We cannot accept that when there was such a change in the order of concepts that nothing happened in the social order. Among other things, the French revolution occurred. Whether it implied another space-time, we don’t know. Mutations occurred in daily life. Let us say that the order of philosophical concepts expressed it [the revolution] in its own way, even if [this order] comes beforehand.

Yet again, we have started from an initial Leibniz-Kant opposition, and we have said that it is undecidable. I cannot decide between the proposition “every proposition is analytical,” and the other proposition in which knowledge proceeds by synthetic propositions. We had to step back. First step back, I have again two antithetical propositions: every determination is conceptual in the last instance, and the Kantian proposition: there are spatio-temporal determinations that are irreducible to the order of the concept. We had to step back again in order to discover a kind of presupposition, notably [that] the Leibniz-Kant opposition is valid only to the extent that we consider that space and time are not at all defined in the same way. It’s odd, this idea that space is that which opens us to an outside; never would someone from the Classical period have said that. It is already an existential relationship with space. Space is the form of what comes to us from outside.

If, for example, I look for the relationship between poetry and philosophy, what does that imply? It implies an open space. If you define space as a milieu of exteriority, it is an open space, not an enclosed space [espace bouclé]. Leibnizian space is an enclosed space, the order of coexistences. Kant’s form is a form that open us up, opens us to an x, it is the form of eruptions. It is already a Romantic space. It is an aesthetic space since it is emancipated from the logical order of the concept. It is a Romantic space because it is the space of overflows. It is the space of the open [l’ouvert]. And when you see in works of certain philosophers who came much later, like Heidegger, a kind of grand song on the theme of the open, you will see that Heidegger calls on Rilke who himself owes this notion of the Open to German Romanticism. You will better understand why Heidegger feels the need to write a book about Kant. He will deeply valorize the theme of the Open. At the same time, poets are inventing it as a rhythmic value or aesthetic value. At the same time, researchers are inventing it as a scientific species.

At this point of my thinking about it, it is very difficult to say who is right and who is wrong. One might like to say that Kant corresponds better to us, goes better with our way of being in space, space as my form of opening. Can we say that Leibniz has been left behind? It is not that simple.
A fourth point. It is perhaps at the farthest extreme of what is new that, in philosophy, occurs what we call the return to [le retour à]. After all, it is never up to an author to push himself as far as he can. It is not Kant who is going as far as is possible for Kant; there will always be post-Kantians who are the great philosophers of German Romanticism. They are the ones who, having pushed Kant as far as possible, experience this strange thing: making a return to Leibniz. [end of the tape] ... I am looking for the deep changes that Kantian philosophy was to bring about both in relation to so-called Classical philosophy and in relation to the philosophy of Leibniz. We have seen a first change concerning space-time. There is a second change, this time concerning the concept of the phenomenon. You are going to see why one results from the other. For quite a long time, the phenomenon was opposed to what, and what did it mean? Very often phenomenon is translated as appearance, appearances. And appearances, let’s say that it is the sensible [le sensible]. The sensible appearance. And appearance is distinguished from what? It forms a doublet, a couple with the correlative of essence. Appearance is opposed to essence. And Platonism will develop a duality of appearance and essence, sensible appearances and intelligible essences. A famous conception results from this: the conception of two worlds. Are there two worlds, the sensible world and the intelligible world? Are we prisoners, through our senses and through our bodies, of a world of appearances? Kant uses the word “phenomenon,” and the reader gets the impression that when he [the reader] tries to situate the old notion of appearances under the Kantian word, it doesn’t work. Isn’t there going to be as important a revolution as for time and space, on the level of the phenomenon? When Kant uses the word “phenomenon,” he loads it with a much more violent meaning: it is not appearance that separates us from essence, it is apparition, that which appears insofar as it appears. The phenomenon in Kant’s work is not appearance, but apparition. Apparition is the manifestation of that which appears insofar as it appears. Why is it immediately linked to the preceding revolution? Because when I say that what appears insofar as it appears, what does the “insofar” [en tant que] mean? It means that that which appears does so necessarily in space and time. This is immediately united to the preceding theses. Phenomenon means: that which appears in space and in time. It no longer means sensible appearance, it means spatio-temporal apparition. What reveals the extent to which this is not the same thing? If I look for the doublet with which apparition is in relation. We have seen that appearance is related to essence, to the point that there are perhaps two worlds, the world of appearances and the world of essences. But apparition is related to what? Apparition is in relation to condition. Something that appears, appears under conditions that are the conditions of its apparition. Conditions are the making-appear of apparition. These are the conditions according to which what appears, appears. Apparition refers to the conditions of the apparition, just as appearance refers to essence. Others will say that apparition refers to meaning [sens]. The doublet is: apparition and meaning of the apparition. Phenomenon is no longer thought as an appearance in relation to its essence, but as an apparition in relation to its condition or its meaning. Yet another thunderclap: there is no longer only one world constituted by that which appears and the meaning of that which appears. What appears no longer refers to essences that would be behind the appearance; that which appears refers to conditions that condition the apparition of what appears. Essence yields to meaning. The concept is no longer the essence of the thing, it is the meaning of the apparition. Understand that this is an entirely new concept in philosophy from which will unfold philosophy’s determination under the name of a new discipline, that of phenomenology. Phenomenology will be the discipline that considers phenomena as apparitions, referring to conditions or to a meaning, instead of considering them as appearances referring to essences. Phenomenology will take as much meaning as you want, but it will at least have this unity, specifically its first great moment will be with Kant who pretends to undertake a phenomenology, precisely because he changes the concept of the phenomenon, making it the object of a phenomenology instead of the object of a discipline of appearances. The first great moment in which phenomenology will be developed as an autonomous discipline will be in Hegel’s famous text, Phenomenology of Spirit. And the word is very peculiar. The Phenomenology of Spirit being precisely the great book that announces the disappearance of the two worlds, there is no more than a single world. Hegel’s formula is: behind the curtain, there is nothing to see. Philosophically that means that the phenomenon is not a mere appearance behind which an essence is located; the phenomenon is an apparition that refers to the conditions of its apparition. There is but one single world. That is the moment when philosophy breaks its final links to theology. Phenomenology’s second moment will be the one in which Husserl renews phenomenology through a theory of apparition and meaning. He will invent a form of logic proper to phenomenology. Things are obviously more complex than that.

I will offer you an extremely simple schema. Kant is the one who broke with the simple opposition between appearance and essence in order to establish a correlation [between] the apparition and conditions of apparition, or apparition-meaning [apparition-sens]. But separating oneself from something is very difficult. Kant preserves something from the former opposition. In Kant, there is a strange thing, the distinction between the phenomenon and the thing in itself. Phenomenon-thing in itself, for Kant, preserves something from the former apparition. But the really innovative aspect of Kant is the conversion of another set of notions, apparition-conditions of the apparition. And the thing in itself is not at all a condition of apparition, but something completely different. And a second correction is this: from Plato to Leibniz, we were not simply told that there are appearances and essences. Moreover, already with Plato there appears a very curious notion that he calls well-founded appearance, that is, essence is hidden from us, but in some ways, appearance expresses it as well. The relation between appearance and essence is a very complex one that Leibniz will try to push in a very strange direction, specifically: he will create from it a theory of symbolization. The Leibnizian theory of symbolization quite singularly prepares the Kantian revolution. The phenomenon symbolizes with essence. This relation of symbolization is no longer that of appearance with essence.

I am trying to continue: there occurs a new disturbance at the level of the conception of the phenomenon. You will see just how it immediately links up with the disturbance of space-time. Finally there is a fundamental disturbance at the level of subjectivity.
There again it’s a strange story. When does this notion of subjectivity take off? Leibniz pushes the presuppositions of classical philosophy as far as he can, down the paths of genius and delirium. From a perspective like that of Leibniz, one really has very little choice. These are philosophies of creation. What does a philosophy of creation mean? These are philosophies that have maintained a certain alliance with theology, to the point that even atheists, if indeed they are that, will pass by way of God. Obviously, that does not take place on the level of the word. As a result of this alliance that they have with theology, they pass by way of God to some extent. That is, their point of view is fundamentally creationist. And even philosophers who do something other than creationism, that is, who are not interested or who replace the concept of creation with something else, they fight against creation according to the concept of creation. In all cases, the point that they start from is infinity. Philosophers have an innocent way of thinking starting from infinity, and they give themselves to infinity. There was infinity everywhere, in God and in the world. That let them undertake things like infinitesimal analysis. An innocent way of thinking starting from infinity means a world of creation. They could go quite far, but not all the way. Subjectivity. To move in this direction, a completely different aggregate was necessary. Why couldn’t they go all the way toward a discovery of subjectivity? Still they went very far.

Descartes invents his own concept, the famous “I think, therefore I am,” notably the discovery of subjectivity or the thinking subject. The discovery that thought refers to a subject. A Greek would not even have understood what was being said with the idea of a thinking subject. Leibniz will not forget it, for there is a Leibnizian subjectivity. And generally we define modern philosophy with the discovery of subjectivity. They could not go all the way through this discovery of subjectivity for a very simple reason: however far they might go in their explorations, this subjectivity can only be posited as created, precisely because they have an innocent way of thinking starting from infinity.
The thinking subject, insofar as the finite subject can be thought of as created, created by God. Thought referring to the subject can only be thought as created: what does that mean? It means that the thinking subject is substance, is a thing. Res. It is not an extended thing, as Descartes says it’s a thinking thing. It is an unextended thing, but it is a thing, a substance, and it has the status of created things, it is a created thing, a created substance. Does that block them? You will tell me that it’s not difficult, they had only to put the thinking subject in the place of God, no interest in exchanging places. In that event, one has to speak of an infinite thinking subject in relation to which finite thinking subjects would themselves be created substances. Nothing would be gained. Thus, their strength, specifically this innocent way of thinking according to infinity, leads them to the threshold of subjectivity and prevents them from crossing through.

What does Kant’s rupture with Descartes consist in? What is the difference between the Kantian cogito and the Cartesian cogito? For Kant, the thinking subject is not a substance, not determined as a thinking thing. It is going to be pure form, form of the apparition of everything that appears. In other words, it is the condition of apparition of all that appears in space and in time. Yet another thunderclap. Kant undertakes to find a new relation of thought with space and time.
Pure form, empty form, there Kant becomes splendid. He goes so far as to say of the “I think” that it is the poorest thought. Only, it is the condition of any thought about any one thing. “I think” is the condition of all thought about any one thing that appears in space and in time, but itself is an empty form that conditions every apparition. That becomes a severe world, a desert world. The desert grows. What has disappeared is the world inhabited by the divine, the infinite, and it became the world of men. What disappeared is the problem of creation, replaced by an completely different problem that will be the problem of Romanticism, specifically the problem of founding [fondement]. The problem of founding or of foundation [fondation]. Now there arises a clever thought, puritanical, desert-like, that wonders, once it’s admitted that the world exists and that it appears, how to found it?
The question of creation has been rejected, but now the problem of founding arrives. If there is really a philosopher who spoke the discourse of God, it was Leibniz. Now the model philosopher has become the hero, the founding hero. He is the one who founds within an existing world, not the one who creates the world. What is foundational [fondateur] is that which conditions the condition of what appears in space and in time. Everything is linked there. A change in the notion of space-time, a change in the notion of the subject. The thinking subject as pure form will only be the act of founding the world such as it appears and knowledge of the world such as it appears. This is an entirely new undertaking.

A year ago, I tried to distinguish the Classical artist from the Romantic artist. The Classical and the Baroque are two poles of the same enterprise. I was saying that the Classical artist is one who organized milieus and who, to some extent, is in the situation of God, this is creation. The Classical artist never stops undertaking creation anew, by organizing milieus, and never ceases to pass from one milieu to another. He passes from water to earth, he separates the earth and the waters, exactly God’s task in creation. He poses a kind of challenge to God: they are going to do just as much, and that is what the Classical artist is. The Romantic at first glance would be less crazy; his problem is that of founding. It is no longer the problem of the world, but one of the earth. It is no longer the problem of milieu, but one of territory. To leave one’s territory in order to find the center of the earth, that’s what founding is. The Romantic artist renounced creating because there is a much more heroic task, and this heroic task is foundation. It is no longer creation and milieu; it’s: I am leaving my territory. Empedocles. The founding is in the bottomless [Le fondement est dans le sans fond]. All post-Kantian philosophy from Schelling on will arise around this kind of abundant concept or the bottom, the fundament founding, the bottomless. That is always what the lied is, the tracing of a territory haunted by the hero, and the hero leaves, departs for the center of the earth, he deserts. The song of the earth. Mahler. The opposition maintained between the tune about the territory and the song of the earth.

The musical doublet territory-earth corresponds exactly to what in philosophy is the phenomenon apparition and the condition of apparition. Why do they abandon the point of view of creation?
Why is the hero not someone who creates, but someone who founds, and why isn’t it the final word? If there were a moment in which Western thought was a bit tired of taking itself for God and of thinking in terms of creation, the seed must be here. Does the image of heroic thought suit us still? All that is finished. Understand the enormous importance of this substitution of the form of the ego [forme du moi] by the thinking subject. The thinking substance was still the point of view of God, it’s a finite substance, but created according to the infinite, created by God.
Whereas when Kant tells us that the thinking subject is not a thing, he well understands a created thing, a form that conditions the apparition of all that appears in space and in time, that is, it is the form of founding. What is he in the process of doing? He institutes the finite ego [le moi fini] as first principle.
Doing that is frightening. Kant’s history depends greatly on the reform. The finite ego is the true founding. Thus the first principle becomes finitude. For the Classics, finitude is a consequence, the limitation of something infinite. The created world is finite, the Classics tell us, because it is limited. The finite ego founds the world and knowledge of the world because the finite ego is itself the constitutive founding of what appears. In other words, it is finitude that is the founding of the world. The relations of the infinite to the finite shift completely. The finite will no longer be a limitation of the infinite; rather, the infinite will be an overcoming [dépassement] of the finite. Moreover, it is a property of the finite to surpass and go beyond itself. The notion of self-overcoming [auto-dépassement] begins to be developed in philosophy. It will traverse all of Hegel and will reach into Nietzsche. The infinite is no longer separable from an act of overcoming finitude because only finitude can overcome itself. Everything called dialectic and the operation of the infinite to be transformed therein, the infinite becoming and become the act through which finitude overcomes itself by constituting or by founding the world. In that way, the infinite is subordinated to the act of the finite. What results from this? Fichte has an exemplary page for the Kantian polemic with Leibniz. Here is what Fichte tells us: I can say A is A, but this is only a hypothetical proposition. Why? Because it presupposes “if there is A.” If A is, A is A, but if there is nothing, A is not A. This is very interesting because he is in the act of overthrowing the principle of identity. He says that the principle of identity is a hypothetical rule. Hence he launches his great theme: to overcome hypothetical judgment to go toward what he calls “thetic” judgment (le jugement thétique]. To go beyond hypothesis toward thesis. Why is it that A is A, if A does exist because finally the proposition A is A is not at all a final principle or a first principle? It refers to something deeper, specifically that one must say that A is A because it is thought. Specifically, what founds the identity of things that are thought is the identity of the thinking subject. Moreover, the identity of the thinking subject is the identity of the finite ego. Thus the first principle is not that A is A, but that ego equals ego. German philosophy will encumber its books with the magic formula: ego equals ego. Why is this formula so bizarre? It is a synthetic identity because ego equals ego marks the identity of the ego that thinks itself as the condition of all that appears in space and in time, and [illegible] that appears in space and in time itself. In this there is a synthesis that is the synthesis of finitude, notably the thinking subject, primary ego, form of all that appears in space and time, must also appear in space and in time, that is ego equals ego. Hence the synthetic identity of the finite ego replaces the infinite analytic identity of God.

I will finish with two things: what could it mean to be Leibnizian today? It’s that Kant absolutely created a kind of radically new conceptual aggregate. These are completely new philosophical conceptual coordinates. But in the case of these new coordinates, Kant in one sense renews everything, but there are all sorts of things that are not elucidated in what he proposes. An example: what exact relation is there between the condition of the phenomenon itself insofar as it appears?
I will review: The thinking ego, the finite ego, conditions, founds the phenomenal apparition. The phenomenon appears in space and in time. How is this possible? What does this relation of conditioning mean? In other words, the “I think” is a form of knowledge that conditions the apparition of all that appears.
How is this possible, what is the relation between the conditioned and the condition? The condition is the form of “I think.” Kant is quite annoyed. He says that this is a fact of reason, he who had so demanded that the question be elevated to the state quid juris, now he invokes what he himself call a factum: the finite ego is so constituted that what appears for it, what appears to it, conforms to the conditions of the apparition such that its very own thought determines it. Kant will say that this agreement of the conditioned and the condition can only be explained by a harmony of our faculties, specifically our passive sensibility and our active thought. What Kant does is pathetic; he is in the process of sneaking God in behind our backs. What guarantees this harmony? He will say it himself: the idea of God.
What will the post-Kantians do? They are philosophers who say above all that Kant is inspired [genial], but still, we cannot remain in an exterior relation of the condition and conditioned because if we remain in this relation of fact, specifically that there is a harmony between the conditioned and the condition and that’s that, then we are obliged to resuscitate God as a guarantee of harmony.
Kant still remains in a viewpoint which is that of exterior conditioning, yet he does not reach a true viewpoint of genesis. It would require showing how conditions of apparition are at the same time genetic elements of what appears. What is necessary to show that? One has to take seriously one of the Kantian revolutions that Kant left aside, notably that the infinite is truly the act of finitude insofar as it overcomes itself. Kant had left that aside because he was content with a reduction of the infinite to the indefinite.
To return to a strong conception of the infinite, but in the manner of the Classics, one has to show that the infinite is an infinite in the strong sense, but as such, it is the act of finitude insofar as it overcomes itself, and in so doing, it constitutes the world of apparitions. This is to substitute the viewpoint of genesis for the viewpoint of the condition. Moreover, doing that means returning to Leibniz, but on bases other than Leibniz’s. All the elements to create a genesis such as the post-Kantians demand it, all the elements are virtually in Leibniz. The idea of a differential of consciousness, at that point the “I think” of consciousness must bathe in an unconscious, and there must be an unconscious of thought as such. The Classics would have said that there is only God who goes beyond thought. Kant would say that there is thought as a form of the finite ego. In this, one must almost summon an unconscious to thought that would contain the differentials of what appears in thought. In other words, which performs the genesis of the conditioned as a function of the condition. That will be Fichte’s great task, taken up again by Hegel on other bases.

You see henceforth that at the limit, they can rediscover all of Leibniz. And us? A lot has taken place. So I define philosophy as an activity that consists in creating concepts. To create concepts is as creative as art. But like all things, the creation of concepts occurs in correspondence with other modes of creation. In which sense [do] we need concepts? It’s a material existence, and concepts are spiritual animals [bêtes spirituelles). How do these kinds of appeals to concepts occur? The old concepts will serve, provided that they are taken up within new conceptual coordinates. There is a philosophical sensibility which is the art of evaluating the consistency of an aggregate of concepts. Does it work? How does it function? Philosophy does not have a history separate from the rest. Nothing, never is anyone overcome [dépassé]. We are never left behind in what we create. We are always left behind in what we do not create, by definition. What happened in our contemporary philosophy? I believe that the philosopher ceased taking himself for a founding hero, in the Romantic manner. What was fundamental in what we can call, generally, our modernity, was this kind of bankruptcy of Romanticism in our estimation. Hölderlin and Novalis no longer work for us and only work for us within the framework of new coordinates. We are finished taking ourselves for heroes. The model of the philosopher and artist is no longer God at all insofar as he [or she] proposes to create the equivalent of a world. This is no longer the hero insofar as he [or she] proposes to found a world, for it has become something else. There is a small text by Paul Klee in which he tries to say how he sees his own difference even from earlier painters. One can no longer go towards the motif. There is a kind of continuous flow, and this flow has twists and turns. Then the flow no longer passes in that direction. The coordinates of painting have changed.

Leibniz is infinite analysis, Kant is the grand synthesis of finitude. Assuming that today we are in the age of the synthesizer, that is something else entirely.