The Mystery of Modality. Thought of the Day 78.0


The ‘metaphysical’ notion of what would have been no matter what (the necessary) was conflated with the epistemological notion of what independently of sense-experience can be known to be (the a priori), which in turn was identified with the semantical notion of what is true by virtue of meaning (the analytic), which in turn was reduced to a mere product of human convention. And what motivated these reductions?

The mystery of modality, for early modern philosophers, was how we can have any knowledge of it. Here is how the question arises. We think that when things are some way, in some cases they could have been otherwise, and in other cases they couldn’t. That is the modal distinction between the contingent and the necessary.

How do we know that the examples are examples of that of which they are supposed to be examples? And why should this question be considered a difficult problem, a kind of mystery? Well, that is because, on the one hand, when we ask about most other items of purported knowledge how it is we can know them, sense-experience seems to be the source, or anyhow the chief source of our knowledge, but, on the other hand, sense-experience seems able only to provide knowledge about what is or isn’t, not what could have been or couldn’t have been. How do we bridge the gap between ‘is’ and ‘could’? The classic statement of the problem was given by Immanuel Kant, in the introduction to the second or B edition of his first critique, The Critique of Pure Reason: ‘Experience teaches us that a thing is so, but not that it cannot be otherwise.’

Note that this formulation allows that experience can teach us that a necessary truth is true; what it is not supposed to be able to teach is that it is necessary. The problem becomes more vivid if one adopts the language that was once used by Leibniz, and much later re-popularized by Saul Kripke in his famous work on model theory for formal modal systems, the usage according to which the necessary is that which is ‘true in all possible worlds’. In these terms the problem is that the senses only show us this world, the world we live in, the actual world as it is called, whereas when we claim to know about what could or couldn’t have been, we are claiming knowledge of what is going on in some or all other worlds. For that kind of knowledge, it seems, we would need a kind of sixth sense, or extrasensory perception, or nonperceptual mode of apprehension, to see beyond the world in which we live to these various other worlds.

Kant concludes, that our knowledge of necessity must be what he calls a priori knowledge or knowledge that is ‘prior to’ or before or independent of experience, rather than what he calls a posteriori knowledge or knowledge that is ‘posterior to’ or after or dependant on experience. And so the problem of the origin of our knowledge of necessity becomes for Kant the problem of the origin of our a priori knowledge.

Well, that is not quite the right way to describe Kant’s position, since there is one special class of cases where Kant thinks it isn’t really so hard to understand how we can have a priori knowledge. He doesn’t think all of our a priori knowledge is mysterious, but only most of it. He distinguishes what he calls analytic from what he calls synthetic judgments, and holds that a priori knowledge of the former is unproblematic, since it is not really knowledge of external objects, but only knowledge of the content of our own concepts, a form of self-knowledge.

We can generate any number of examples of analytic truths by the following three-step process. First, take a simple logical truth of the form ‘Anything that is both an A and a B is a B’, for instance, ‘Anyone who is both a man and unmarried is unmarried’. Second, find a synonym C for the phrase ‘thing that is both an A and a B’, for instance, ‘bachelor’ for ‘one who is both a man and unmarried’. Third, substitute the shorter synonym for the longer phrase in the original logical truth to get the truth ‘Any C is a B’, or in our example, the truth ‘Any bachelor is unmarried’. Our knowledge of such a truth seems unproblematic because it seems to reduce to our knowledge of the meanings of our own words.

So the problem for Kant is not exactly how knowledge a priori is possible, but more precisely how synthetic knowledge a priori is possible. Kant thought we do have examples of such knowledge. Arithmetic, according to Kant, was supposed to be synthetic a priori, and geometry, too – all of pure mathematics. In his Prolegomena to Any Future Metaphysics, Kant listed ‘How is pure mathematics possible?’ as the first question for metaphysics, for the branch of philosophy concerned with space, time, substance, cause, and other grand general concepts – including modality.

Kant offered an elaborate explanation of how synthetic a priori knowledge is supposed to be possible, an explanation reducing it to a form of self-knowledge, but later philosophers questioned whether there really were any examples of the synthetic a priori. Geometry, so far as it is about the physical space in which we live and move – and that was the original conception, and the one still prevailing in Kant’s day – came to be seen as, not synthetic a priori, but rather a posteriori. The mathematician Carl Friedrich Gauß had already come to suspect that geometry is a posteriori, like the rest of physics. Since the time of Einstein in the early twentieth century the a posteriori character of physical geometry has been the received view (whence the need for border-crossing from mathematics into physics if one is to pursue the original aim of geometry).

As for arithmetic, the logician Gottlob Frege in the late nineteenth century claimed that it was not synthetic a priori, but analytic – of the same status as ‘Any bachelor is unmarried’, except that to obtain something like ‘29 is a prime number’ one needs to substitute synonyms in a logical truth of a form much more complicated than ‘Anything that is both an A and a B is a B’. This view was subsequently adopted by many philosophers in the analytic tradition of which Frege was a forerunner, whether or not they immersed themselves in the details of Frege’s program for the reduction of arithmetic to logic.

Once Kant’s synthetic a priori has been rejected, the question of how we have knowledge of necessity reduces to the question of how we have knowledge of analyticity, which in turn resolves into a pair of questions: On the one hand, how do we have knowledge of synonymy, which is to say, how do we have knowledge of meaning? On the other hand how do we have knowledge of logical truths? As to the first question, presumably we acquire knowledge, explicit or implicit, conscious or unconscious, of meaning as we learn to speak, by the time we are able to ask the question whether this is a synonym of that, we have the answer. But what about knowledge of logic? That question didn’t loom large in Kant’s day, when only a very rudimentary logic existed, but after Frege vastly expanded the realm of logic – only by doing so could he find any prospect of reducing arithmetic to logic – the question loomed larger.

Many philosophers, however, convinced themselves that knowledge of logic also reduces to knowledge of meaning, namely, of the meanings of logical particles, words like ‘not’ and ‘and’ and ‘or’ and ‘all’ and ‘some’. To be sure, there are infinitely many logical truths, in Frege’s expanded logic. But they all follow from or are generated by a finite list of logical rules, and philosophers were tempted to identify knowledge of the meanings of logical particles with knowledge of rules for using them: Knowing the meaning of ‘or’, for instance, would be knowing that ‘A or B’ follows from A and follows from B, and that anything that follows both from A and from B follows from ‘A or B’. So in the end, knowledge of necessity reduces to conscious or unconscious knowledge of explicit or implicit semantical rules or linguistics conventions or whatever.

Such is the sort of picture that had become the received wisdom in philosophy departments in the English speaking world by the middle decades of the last century. For instance, A. J. Ayer, the notorious logical positivist, and P. F. Strawson, the notorious ordinary-language philosopher, disagreed with each other across a whole range of issues, and for many mid-century analytic philosophers such disagreements were considered the main issues in philosophy (though some observers would speak of the ‘narcissism of small differences’ here). And people like Ayer and Strawson in the 1920s through 1960s would sometimes go on to speak as if linguistic convention were the source not only of our knowledge of modality, but of modality itself, and go on further to speak of the source of language lying in ourselves. Individually, as children growing up in a linguistic community, or foreigners seeking to enter one, we must consciously or unconsciously learn the explicit or implicit rules of the communal language as something with a source outside us to which we must conform. But by contrast, collectively, as a speech community, we do not so much learn as create the language with its rules. And so if the origin of modality, of necessity and its distinction from contingency, lies in language, it therefore lies in a creation of ours, and so in us. ‘We, the makers and users of language’ are the ground and source and origin of necessity. Well, this is not a literal quotation from any one philosophical writer of the last century, but a pastiche of paraphrases of several.

La Mettrie’s Man-Machine


Philosophers’ theories regarding the human soul? Basically there are just two of them: the first and older of the two is materialism; the second is spiritualism.

The metaphysicians who implied that matter might well have the power to think didn’t disgrace themselves as thinkers. Why not? Because they had the advantage (for in this case it is one) of expressing themselves badly. To ask whether unaided matter can think is like asking whether unaided matter can indicate the time. It’s clear already that we aren’t going to hit the rock on which Locke had the bad luck to come to grief in his speculations about whether there could be thinking matter.

The Leibnizians with their ‘monads’ have constructed an unintelligible hypothesis. Rather than materialising the soul, they spiritualised matter. How can we define a being like the so-called ‘monad’ whose nature is absolutely unknown to us?

Descartes and all the Cartesians – among whom Malebranche’s followers have long been included – went wrong in the same way, namely by dogmatising about something of which they knew nothing. They admitted two distinct substances in man, as if they had seen and counted them!

man machine

Weyl and Automorphism of Nature. Drunken Risibility.


In classical geometry and physics, physical automorphisms could be based on the material operations used for defining the elementary equivalence concept of congruence (“equality and similitude”). But Weyl started even more generally, with Leibniz’ explanation of the similarity of two objects, two things are similar if they are indiscernible when each is considered by itself. Here, like at other places, Weyl endorsed this Leibnzian argument from the point of view of “modern physics”, while adding that for Leibniz this spoke in favour of the unsubstantiality and phenomenality of space and time. On the other hand, for “real substances” the Leibnizian monads, indiscernability implied identity. In this way Weyl indicated, prior to any more technical consideration, that similarity in the Leibnizian sense was the same as objective equality. He did not enter deeper into the metaphysical discussion but insisted that the issue “is of philosophical significance far beyond its purely geometric aspect”.

Weyl did not claim that this idea solves the epistemological problem of objectivity once and for all, but at least it offers an adequate mathematical instrument for the formulation of it. He illustrated the idea in a first step by explaining the automorphisms of Euclidean geometry as the structure preserving bijective mappings of the point set underlying a structure satisfying the axioms of “Hilbert’s classical book on the Foundations of Geometry”. He concluded that for Euclidean geometry these are the similarities, not the congruences as one might expect at a first glance. In the mathematical sense, we then “come to interpret objectivity as the invariance under the group of automorphisms”. But Weyl warned to identify mathematical objectivity with that of natural science, because once we deal with real space “neither the axioms nor the basic relations are given”. As the latter are extremely difficult to discern, Weyl proposed to turn the tables and to take the group Γ of automorphisms, rather than the ‘basic relations’ and the corresponding relata, as the epistemic starting point.

Hence we come much nearer to the actual state of affairs if we start with the group Γ of automorphisms and refrain from making the artificial logical distinction between basic and derived relations. Once the group is known, we know what it means to say of a relation that it is objective, namely invariant with respect to Γ.

By such a well chosen constitutive stipulation it becomes clear what objective statements are, although this can be achieved only at the price that “…we start, as Dante starts in his Divina Comedia, in mezzo del camin”. A phrase characteristic for Weyl’s later view follows:

It is the common fate of man and his science that we do not begin at the beginning; we find ourselves somewhere on a road the origin and end of which are shrouded in fog.

Weyl’s juxtaposition of the mathematical and the physical concept of objectivity is worthwhile to reflect upon. The mathematical objectivity considered by him is relatively easy to obtain by combining the axiomatic characterization of a mathematical theory with the epistemic postulate of invariance under a group of automorphisms. Both are constituted in a series of acts characterized by Weyl as symbolic construction, which is free in several regards. For example, the group of automorphisms of Euclidean geometry may be expanded by “the mathematician” in rather wide ways (affine, projective, or even “any group of transformations”). In each case a specific realm of mathematical objectivity is constituted. With the example of the automorphism group Γ of (plane) Euclidean geometry in mind Weyl explained how, through the use of Cartesian coordinates, the automorphisms of Euclidean geometry can be represented by linear transformations “in terms of reproducible numerical symbols”.

For natural science the situation is quite different; here the freedom of the constitutive act is severely restricted. Weyl described the constraint for the choice of Γ at the outset in very general terms: The physicist will question Nature to reveal him her true group of automorphisms. Different to what a philosopher might expect, Weyl did not mention, the subtle influences induced by theoretical evaluations of empirical insights on the constitutive choice of the group of automorphisms for a physical theory. He even did not restrict the consideration to the range of a physical theory but aimed at Nature as a whole. Still basing on his his own views and radical changes in the fundamental views of theoretical physics, Weyl hoped for an insight into the true group of automorphisms of Nature without any further specifications.

Leibniz’s Compossibility and Compatibility


Leibniz believed in discovering a suitable logical calculus of concepts enabling its user to solve any rational question. Assuming that it is done he was in power to sketch the full ontological system – from monads and qualities to the real world.

Thus let some logical calculus of concepts (names?, predicates?) be given. Cn is its connected consequence operator, whereas – for any x – Th(x) is the Cn-theory generated by x.

Leibniz defined modal concepts by the following metalogical conditions:

M(x) :↔ ⊥ ∉ Th(x)

x is possible (its theory is consistent)

L(x) :↔ ⊥ ∈ Th(¬x)

x is necessary (its negation is impossible)

C(x,y) :↔ ⊥ ∉ Cn(Th(x) ∪ Th(y))

x and y are compossible (their common theory is consistent).

Immediately we obtain Leibnizian ”soundness” conditions:

C(x, y) ↔ C(y, x) Compossibility relation is symmetric.

M(x) ↔ C(x, x) Possibility means self-compossibility.

C(x, y) → M(x)∧M(y) Compossibility implies possibility.

When can the above implication be reversed?

Onto\logical construction

Observe that in the framework of combination ontology we have already defined M(x) in a way respecting M(x) ↔ C(x, x).

On the other hand, between MP( , ) and C( , ) there is another relation, more fundamental than compossibility. It is so-called compatibility relation. Indeed, putting

CP(x, y) :↔ MP(x, y) ∧ MP(y, x) – for compatibility, and C(x,y) :↔ M(x) ∧ M(y) ∧ CP(x,y) – for compossibility

we obtain a manageable compossibility relation obeying the above Leibniz’s ”soundness” conditions.

Wholes are combinations of compossible collections, whereas possible worlds are obtained by maximalization of wholes.

Observe that we start with one basic ontological making: MP(x, y) – modality more fundamental than Leibnizian compossibility, for it is definable in two steps. Observe also that the above construction can be done for making impossible and to both basic ontological modalities as well (producing quite Hegelian output in this case!).

Conjuncted: Indiscernibles – Philosophical Constructibility. Thought of the Day 48.1

Simulated Reality

Conjuncted here.

“Thought is nothing other than the desire to finish with the exorbitant excess of the state” (Being and Event). Since Cantor’s theorem implies that this excess cannot be removed or reduced to the situation itself, the only way left is to take control of it. A basic, paradigmatic strategy for achieving this goal is to subject the excess to the power of language. Its essence has been expressed by Leibniz in the form of the principle of indiscernibles: there cannot exist two things whose difference cannot be marked by a describable property. In this manner, language assumes the role of a “law of being”, postulating identity, where it cannot find a difference. Meanwhile – according to Badiou – the generic truth is indiscernible: there is no property expressible in the language of set theory that characterizes elements of the generic set. Truth is beyond the power of knowledge, only the subject can support a procedure of fidelity by deciding what belongs to a truth. This key thesis is established using purely formal means, so it should be regarded as one of the peak moments of the mathematical method employed by Badiou.

Badiou composes the indiscernible out of as many as three different mathematical notions. First of all, he decides that it corresponds to the concept of the inconstructible. Later, however, he writes that “a set δ is discernible (…) if there exists (…) an explicit formula λ(x) (…) such that ‘belong to δ’ and ‘have the property expressed by λ(x)’ coincide”. Finally, at the outset of the argument designed to demonstrate the indiscernibility of truth he brings in yet another definition: “let us suppose the contrary: the discernibility of G. A formula thus exists λ(x, a1,…, an) with parameters a1…, an belonging to M[G] such that for an inhabitant of M[G] it defines the multiple G”. In short, discernibility is understood as:

  1. constructibility
  2. definability by a formula F(y) with one free variable and no parameters. In this approach, a set a is definable if there exists a formula F(y) such that b is an element of a if F(b) holds.
  3. definability by a formula F (y, z1 . . . , zn) with parameters. This time, a set a is definable if there exists a formula F(y, z1,…, zn) and sets a1,…, an such that after substituting z1 = a1,…, zn = an, an element b belongs to a iff F(b, a1,…, an) holds.

Even though in “Being and Event” Badiou does not explain the reasons for this variation, it clearly follows from his other writings (Alain Badiou Conditions) that he is convinced that these notions are equivalent. It should be emphasized then that this is not true: a set may be discernible in one sense, but indiscernible in another. First of all, the last definition has been included probably by mistake because it is trivial. Every set in M[G] is discernible in this sense because for every set a the formula F(y, x) defined as y belongs to x defines a after substituting x = a. Accepting this version of indiscernibility would lead to the conclusion that truth is always discernible, while Badiou claims that it is not so.

Is it not possible to choose the second option and identify discernibility with definability by a formula with no parameters? After all, this notion is most similar to the original idea of Leibniz intuitively, the formula F(y) expresses a property characterizing elements of the set defined by it. Unfortunately, this solution does not warrant indiscernibility of the generic set either. As a matter of fact, assuming that in ontology, that is, in set theory, discernibility corresponds to constructibility, Badiou is right that the generic set is necessarily indiscernible. However, constructibility is a highly technical notion, and its philosophical interpretation seems very problematic. Let us take a closer look at it.

The class of constructible sets – usually denoted by the letter L – forms a hierarchy indexed or numbered by ordinal numbers. The lowest level L0 is simply the empty set. Assuming that some level – let us denote it by Lα – has already been

constructed, the next level Lα+1 is constructed by choosing all subsets of L that can be defined by a formula (possibly with parameters) bounded to the lower level Lα.

Bounding a formula to Lα means that its parameters must belong to Lα and that its quantifiers are restricted to elements of Lα. For instance, the formula ‘there exists z such that z is in y’ simply says that y is not empty. After bounding it to Lα this formula takes the form ‘there exists z in Lα such that z is in y’, so it says that y is not empty, and some element from Lα witnesses it. Accordingly, the set defined by it consists of precisely those sets in Lα that contain an element from Lα.

After constructing an infinite sequence of levels, the level directly above them all is simply the set of all elements constructed so far. For example, the first infinite level Lω consists of all elements constructed on levels L0, L1, L2,….

As a result of applying this inductive definition, on each level of the hierarchy all the formulas are used, so that two distinct sets may be defined by the same formula. On the other hand, only bounded formulas take part in the construction. The definition of constructibility offers too little and too much at the same time. This technical notion resembles the Leibnizian discernibility only in so far as it refers to formulas. In set theory there are more notions of this type though.

To realize difficulties involved in attempts to philosophically interpret constructibility, one may consider a slight, purely technical, extension of it. Let us also accept sets that can be defined by a formula F (y, z1, . . . , zn) with constructible parameters, that is, parameters coming from L. Such a step does not lead further away from the common understanding of Leibniz’s principle than constructibility itself: if parameters coming from lower levels of the hierarchy are admissible when constructing a new set, why not admit others as well, especially since this condition has no philosophical justification?

Actually, one can accept parameters coming from an even more restricted class, e.g., the class of ordinal numbers. Then we will obtain the notion of definability from ordinal numbers. This minor modification of the concept of constructibility – a relaxation of the requirement that the procedure of construction has to be restricted to lower levels of the hierarchy – results in drastic consequences.

Anti-Haecceitism. Thought of the Day 45.0


; Conc is the property of being concurrent, Red is the property of definiteness, and Heavy is the property of vividness.

In the language of modern metaphysics, w and w′ above are qualitatively indiscernible. And anti-haecceitism is the doctrine which says that qualitatively indiscernible worlds are identical. So, we immediately see a problem looming.

But why accept anti-haecceitism? The best reasons focus on physics. Just as the debate between Leibniz and Newton’s followers focused on physics, the strongest arguments still against haecceitism come from physics. Anti-haecceitism as understood here concerns the identity of indiscernible (“isomorphic”) worlds or “situations” or “states”. In many areas of physics, including statistical physics, spacetime physics and quantum theory, the physics tells us that certain “indiscernible situations” are in fact literally identical.

A simple example comes from the statistical physics of “indiscernibile particles”. Consider a box, partitioned into Left-side and Right-side (L and R), and containing two indiscernible particles. One naively thinks this permits four distinct states or situations: i.e., both in L; both in R, and one in L and one in R. However, physics tells us that there are only three states, not four, and we might denote these: S2,0, S1,1, S0,2. The state S1,1, i.e., where “one is L and one is R”, is a single state; there are not two distinct possibilities. The correct description of S1,1 uses existential quantifiers:

∃x ∃y (x ≠ y ∧ Lx ∧ Ry)

One can (syntactically) introduce labels for the particles, say a, b. One can do this in two ways, to obtain:

a ≠ b ∧ La ∧ Rb

b ≠ a ∧ Lb ∧ Ra

But this labelling is purely representational, and not in any way fixed by the physical state S1,1 itself. So, there are distinct indiscernible objects in “situations” or states.

From spacetime physics, consider the principle sometimes called “Leibniz equivalence” (Norton). A formulation (but under a different name) is given in Wald’s monograph General Relativity. Wald’s formulation of Leibniz equivalence is, essentially, this:

isomorphic spacetime models represent the same physical world.

For example, let

S = (M, g, . . . )

be a spacetime model with carrier set |M| of points. (i.e., M is the underlying manifold.) Then Leibniz Equivalence implies:

If π : |M| → |M| is any bijection, then πS and S represent

the same world. There are many other examples, including examples from quantum theory. Consequently, independently of our pre-theoretic considerations concerning modality, it seems to me that our best physics – statistical physics, relativity and quantum theory – is telling us that anti-haecceitism is true: given a structure A which represents a world w, any permuted copy πA should somehow represent the same world, w.

Infinitesimal and Differential Philosophy. Note Quote.


If difference is the ground of being qua becoming, it is not difference as contradiction (Hegel), but as infinitesimal difference (Leibniz). Accordingly, the world is an ideal continuum or transfinite totality (Fold: Leibniz and the Baroque) of compossibilities and incompossibilities analyzable into an infinity of differential relations (Desert Islands and Other Texts). As the physical world is merely composed of contiguous parts that actually divide until infinity, it finds its sufficient reason in the reciprocal determination of evanescent differences (dy/dx, i.e. the perfectly determinable ratio or intensive magnitude between indeterminate and unassignable differences that relate virtually but never actually). But what is an evanescent difference if not a speculation or fiction? Leibniz refuses to make a distinction between the ontological nature and the practical effectiveness of infinitesimals. For even if they have no actuality of their own, they are nonetheless the genetic requisites of actual things.

Moreover, infinitesimals are precisely those paradoxical means through which the finite understanding is capable of probing into the infinite. They are the elements of a logic of sense, that great logical dream of a combinatory or calculus of problems (Difference and Repetition). On the one hand, intensive magnitudes are entities that cannot be determined logically, i.e. in extension, even if they appear or are determined in sensation only in connection with already extended physical bodies. This is because in themselves they are determined at infinite speed. Is not the differential precisely this problematic entity at the limit of sensibility that exists only virtually, formally, in the realm of thought? Isn’t the differential precisely a minimum of time, which refers only to the swiftness of its fictional apprehension in thought, since it is synthesized in Aion, i.e. in a time smaller than the minimum of continuous time and hence in the interstitial realm where time takes thought instead of thought taking time?

Contrary to the Kantian critique that seeks to eliminate the duality between finite understanding and infinite understanding in order to avoid the contradictions of reason, Deleuze thus agrees with Maïmon that we shouldn’t speak of differentials as mere fictions unless they require the status of a fully actual reality in that infinite understanding. The alternative between mere fictions and actual reality is a false problem that hides the paradoxical reality of the virtual as such: real but not actual, ideal but not abstract. If Deleuze is interested in the esoteric history of differential philosophy, this is as a speculative alternative to the exoteric history of the extensional science of actual differences and to Kantian critical philosophy. It is precisely through conceptualizing intensive, differential relations that finite thought is capable of acquiring consistency without losing the infinite in which it plunges. This brings us back to Leibniz and Spinoza. As Deleuze writes about the former: no one has gone further than Leibniz in the exploration of sufficient reason [and] the element of difference and therefore [o]nly Leibniz approached the conditions of a logic of thought. Or as he argues of the latter, fictional abstractions are only a preliminary stage for thought to become more real, i.e. to produce an expressive or progressive synthesis: The introduction of a fiction may indeed help us to reach the idea of God as quickly as possible without falling into the traps of infinite regression. In Maïmon’s reinvention of the Kantian schematism as well as in the Deleuzian system of nature, the differentials are the immanent noumena that are dramatized by reciprocal determination in the complete determination of the phenomenal. Even the Kantian concept of the straight line, Deleuze emphasizes, is a dramatic synthesis or integration of an infinity of differential relations. In this way, infinitesimals constitute the distinct but obscure grounds enveloped by clear but confused effects. They are not empirical objects but objects of thought. Even if they are only known as already developed within the extensional becomings of the sensible and covered over by representational qualities, as differences they are problems that do not resemble their solutions and as such continue to insist in an enveloped, quasi-causal state.

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Deleuzian Speculative Philosophy. Thought of the Day 44.0


Deleuze’s version of speculative philosophy is the procedure of counter-effectuation or counter-actualization. In defiance of the causal laws of an actual situation, speculation experiments with the quasi-causal intensities capable of bringing about effects that have their own retro-active power. This is its political import. Leibniz already argued that all things are effects or consequences, even though they do not necessarily have a cause, since the sufficient reason of what exists always lies outside of any actual series and remains virtual. (Leibniz) With the Principle of Sufficient Reason, he thus reinvented the Stoic disjunction between the series of corporeal causes and the series of incorporeal effects. Not because he anticipated the modern bifurcation of given necessary causes (How?) and metaphysically constructed reasons (Why?), but because for him the virtuality of effects is no less real than the interaction of causes. The effect always includes its own cause, since divergent series of events (incompossible worlds) enter into relation with any particular event (in this world), while these interpenetrating series are prior to, and not limited by, actual relations of causality per se. In terms of Deleuze, cause and effect do not share the same temporality. Whereas causes relate to one another in an eternal present (Chronos), effects relate to one another in a past-future purified of the present (Aion). Taken together, these temporalities form the double structure of every event (Logic of Sense). When the night is lit up by a sudden flash of lightning, this is the effect of an intensive, metaphysical becoming that contains its own destiny, integrating a differential potentiality that is irreducible to the physical series of necessary efficient causes that nonetheless participate in it. In order for such a contingent conjugation of events to be actualized (i.e. for effects to influence causes and become individuated in a materially extended state of affairs), however, its impersonal and pre-individual presence must be trusted upon. This takes a speculative investment or amor fati that forms its precursive reason/ground. In Difference and Repetition, Deleuze refers to this will to speculate as the dark precursor which determines the path of a thunderbolt in advance but in reverse, as though intagliated by setting up a communication of difference with difference. It is therefore the differenciator of these differences or in- itself of difference. We find a paradigmatic example of this will to make a difference in William James’ The Will to Believe when he writes: We can and we may, as it were, jump with both feet off the ground into a world of which we trust the other parts to meet our jump and only so can the making of a perfected world of the pluralistic pattern ever take place. Only through our precursive trust in it can it come into being. (James) As Stengers explains, we can and do speculate each time we precursively trust in the possibility of connecting, of entering into a (partial) rapport that cannot be derived from the ground of our current, dominant premises. Or as Deleuze writes: the dark precursor is not the friend (Difference and Repetition) but rather the bad will of a traitor or enemy, since the will does not precede the presubjective cruelty of the event in its involuntariness. At the same time, however, we never jump into a vacuum. We always speculate by the milieu, since a jump in general could never be trusted: If a jump is always situated, it is because its aim is not to escape the ground in order to get access to a higher realm. The jump, connecting this ground, always this ground, with what it was alien to, has the necessity of a response. In other words, the ground must have been given the power to make itself felt as calling for new dimensions. (Stengers) Indeed, if speculative thought cannot be detached from a practical concern, Deleuze at the same time states that [t]here is no other ethic than the amor fati of philosophy. (What is Philosophy?) Speculative reasoning is thus an art of pure expression or efficacy, an art of precipitating events: an art that detects and affirms the possibility of other reasons insisting as so many virtual forces that have not yet had the chance to emerge but whose presence can be trusted upon to make a difference.

In Deleuze’s own terms, there is no such thing as pure reason, only heterogeneous processes of rationalization, of actualizing an irrational potential: There is no metaphysics, but rather a politics of being. (Deleuze) For this reason, the method of speculative philosophy is the method of dramatization. It is a method that distributes events according to a logic that conditions the order of their intelligibility. As such it belongs to what in Difference and Repetition is referred to as the proper order of reasons: differentiation-individuation-dramatisation-differenciation. A book of philosophy, Deleuze famously writes in the preface, should be in part a very particular species of detective novel, in part a kind of science fiction. On the one hand, the creation of concepts cannot be separated from a problematic milieu or stage that matters practically; on the other hand, it seeks to deterritorialize this milieu by speculating on the quasi-causal intensity of its becoming-other.

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Organic and the Orgiastic. Cartography of Ground and Groundlessness in Deleuze and Heidegger. Thought of the Day 43.0


In his last hermeneutical Erörterung of Leibniz, The Principle of Ground, Heidegger traces back metaphysics to its epochal destiny in the twofold or duplicity (Zwiefalt) of Being and Thought and thus follows the ground in its self-ungrounding (zugrundegehen). Since the foundation of thought is also the foundation of Being, reason and ground are not equal but belong together (zusammenhören) in the Same as the ungrounded yet historical horizon of the metaphysical destiny of Being: On the one hand we say: Being and ground: the Same. On the other hand we say: Being: the abyss (Ab-Grund). What is important is to think the univocity (Einsinnigkeit) of both Sätze, those Sätze that are no longer Sätze. In Difference and Repetition, similarly, Deleuze tells us that sufficient reason is twisted into the groundless. He confirms that the Fold (Pli) is the differenciator of difference engulfed in groundlessness, always folding, unfolding, refolding: to ground is always to bend, to curve and recurve. He thus concludes:

Sufficient reason or ground is strangely bent: on the one hand, it leans towards what it grounds, towards the forms of representation; on the other hand, it turns and plunges into a groundless beyond the ground which resists all forms and cannot be represented.

Despite the fundamental similarity of their conclusions, however, our short overview of Deleuze’s transformation of the Principle of Sufficient Reason has already indicated that his argumentation is very different from Heideggerian hermeneutics. To ground, Deleuze agrees, is always to ground representation. But we should distinguish between two kinds of representation: organic or finite representation and orgiastic or infinite representation. What unites the classicisms of Kant, Descartes and Aristotle is that representation retains organic form as its principle and the finite as its element. Here the logical principle of identity always precedes ontology, such that the ground as element of difference remains undetermined and in itself. It is only with Hegel and Leibniz that representation discovers the ground as its principle and the infinite as its element. It is precisely the Principle of Sufficient Reason that enables thought to determine difference in itself. The ground is like a single and unique total moment, simultaneously the moment of the evanescence and production of difference, of disappearance and appearance. What the attempts at rendering representation infinite reveal, therefore, is that the ground has not only an Apollinian, orderly side, but also a hidden Dionysian, orgiastic side. Representation discovers within itself the limits of the organized; tumult, restlessness and passion underneath apparent calm. It rediscovers monstrosity.

The question then is how to evaluate this ambiguity that is essential to the ground. For Heidegger, the Zwiefalt is either naively interpreted from the perspective of its concave side, following the path of the history of Western thought as the belonging together of Being and thought in a common ground; or it is meditated from its convex side, excavating it from the history of the forgetting of Being the decline of the Fold (Wegfall der Zwiefalt, Vorenthalt der Zwiefalt) as the pivotal point of the Open in its unfolding and following the path that leads from the ground to the abyss. Instead of this all or nothing approach, Deleuze takes up the question in a Nietzschean, i.e. genealogical fashion. The attempt to represent difference in itself cannot be disconnected from its malediction, i.e. the moral representation of groundlessness as a completely undifferentiated abyss. As Bergson already observed, representational reason poses the problem of the ground in terms of the alternative between order and chaos. This goes in particular for the kind of representational reason that seeks to represent the irrepresentable: Representation, especially when it becomes infinite, is imbued with a presentiment of groundlessness. Because it has become infinite in order to include difference within itself, however, it represents groundlessness as a completely undifferentiated abyss, a universal lack of difference, an indifferent black nothingness. Indeed, if Deleuze is so hostile to Hegel, it is because the latter embodies like no other the ultimate illusion inseparable from the Principle of Sufficient Reason insofar as it grounds representation, namely that groundlessness should lack differences, when in fact it swarms with them.

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Let us introduce the concept of space using the notion of reflexive action (or reflex action) between two things. Intuitively, a thing x acts on another thing y if the presence of x disturbs the history of y. Events in the real world seem to happen in such a way that it takes some time for the action of x to propagate up to y. This fact can be used to construct a relational theory of space à la Leibniz, that is, by taking space as a set of equitemporal things. It is necessary then to define the relation of simultaneity between states of things.

Let x and y be two things with histories h(xτ) and h(yτ), respectively, and let us suppose that the action of x on y starts at τx0. The history of y will be modified starting from τy0. The proper times are still not related but we can introduce the reflex action to define the notion of simultaneity. The action of y on x, started at τy0, will modify x from τx1 on. The relation “the action of x on y is reflected to x” is the reflex action. Historically, Galileo introduced the reflection of a light pulse on a mirror to measure the speed of light. With this relation we will define the concept of simultaneity of events that happen on different basic things.


Besides we have a second important fact: observation and experiment suggest that gravitation, whose source is energy, is a universal interaction, carried by the gravitational field.

Let us now state the above hypothesis axiomatically.

Axiom 1 (Universal interaction): Any pair of basic things interact. This extremely strong axiom states not only that there exist no completely isolated things but that all things are interconnected.

This universal interconnection of things should not be confused with “universal interconnection” claimed by several mystical schools. The present interconnection is possible only through physical agents, with no mystical content. It is possible to model two noninteracting things in Minkowski space assuming they are accelerated during an infinite proper time. It is easy to see that an infinite energy is necessary to keep a constant acceleration, so the model does not represent real things, with limited energy supply.

Now consider the time interval (τx1 − τx0). Special Relativity suggests that it is nonzero, since any action propagates with a finite speed. We then state

Axiom 2 (Finite speed axiom): Given two different and separated basic things x and y, such as in the above figure, there exists a minimum positive bound for the interval (τx1 − τx0) defined by the reflex action.

Now we can define Simultaneity as τy0 is simultaneous with τx1/2 =Df (1/2)(τx1 + τx0)

The local times on x and y can be synchronized by the simultaneity relation. However, as we know from General Relativity, the simultaneity relation is transitive only in special reference frames called synchronous, thus prompting us to include the following axiom:

Axiom 3 (Synchronizability): Given a set of separated basic things {xi} there is an assignment of proper times τi such that the relation of simultaneity is transitive.

With this axiom, the simultaneity relation is an equivalence relation. Now we can define a first approximation to physical space, which is the ontic space as the equivalence class of states defined by the relation of simultaneity on the set of things is the ontic space EO.

The notion of simultaneity allows the analysis of the notion of clock. A thing y ∈ Θ is a clock for the thing x if there exists an injective function ψ : SL(y) → SL(x), such that τ < τ′ ⇒ ψ(τ) < ψ(τ′). i.e.: the proper time of the clock grows in the same way as the time of things. The name Universal time applies to the proper time of a reference thing that is also a clock. From this we see that “universal time” is frame dependent in agreement with the results of Special Relativity.