Self-Causation, Time, and Quantum Physics

"The future is not what it used to be."
(Paul Valéry)

1. Introduction: Self-causation from Plotinus to Wheeler
A recurrent theme on this blog is the idea that we need some notion of self-causation in order to answer Leibniz's famous question: "Why is there something rather than nothing?" If we define "reality" as the totality of what exists (including past and future existence), then by definition nothing exists outside of reality (not even "nothing"). If we then presuppose the Principle of Sufficient Reason – that there is a sufficient reason for every fact, including the fact that reality exists – then it follows that the reason for reality's existence must lie within reality itself, since there is nothing outside it. And since we generally call the reason why something exists the cause of that something, we must conclude that reality has to be self-causing. In this post I want to investigate the possibility of self-causation in relation to time. 

Can reality bootstrap itself into existence?

1.1 Physicalism and the fig-leaf conception of self-causation
Before going more deeply into the topic of this post, let me first say a few words about the controversial concept of self-causation, which is bound to raise eyebrows. Let me just note that by "self-causation" I mean roughly the same as what contemporary thinkers mean by "explanatory self-subsumption" (Robert Nozick), "self-explanation" (Nicholas Rescher), "cosmic bootstrapping" (Peter Atkins), and "self-excitation / self-synthesis" (John Wheeler). All these thinkers agree with the point made above: that since there is nothing outside of reality as a whole, the reason for its existence must lie within itself, such that reality must ultimately be understood as self-producing. So why don't these thinkers just use the term "self-causation", which is after all the traditional term of art for what is meant here? Premodern and early modern philosophers, from Plotinus to Spinoza, had no qualms in speaking of God as being self-caused (causa sui). So what has changed in the meantime?

What has changed, of course, is the rise of physicalism as the dominant ontology of the modern age, due to the huge experimental successes of mathematical physics and the victory of Neo-Darwinism. As a result, the concept of causation has become virtually synonymous with "physical causation". And if physical causation is the only form of causation around, then clearly self-causation doesn't make much sense (or does it? see the discussion below about retrocausation in quantum physics). Contemporary thinkers have become so imbibed with physicalism as the dominant ontology that they consciously or unconsciously – even if they explicitly reject physicalism! – adopt the physicalist ban on self-causation and use fig leaf notions in its stead, such as "explanatory self-subsumption", "self-explanation", "cosmic bootstrapping", etc.

At the same time, however, we should note that physicalism is currently going through a deepening crisis, mainly brought on by the troublesome phenomenon of consciousness which refuses complete reduction to a physicalist framework. This crisis of physicalism means that the concept of self-causation becomes somewhat less of taboo: it gets a second chance. (See e.g. philosopher John Leslie who, as a Neoplatonizing Spinozist, is quite happy to invoke self-causation.) The crucial role of consciousness in bringing on this crisis makes one wonder if perhaps consciousness holds the key to understanding the self-causation of reality... But this is something I will discuss further in my next post.

1.2 Self-causation and the problem of time
In this post I will focus on a somewhat more specialized topic: the possibility of self-causation in relation to time. As a process in time, self-causation is clearly impossible. As I will argue below, the self-causing entity would either have to precede itself in time or instantaneously emerge in time from out of nowhere – two possibilities which are equally absurd. So if we need self-causation in order to explain reality's existence, then it seems we must be dealing with timeless self-causation. This, of course, was one of the reasons why the philosophical tradition from Plotinus to Hegel conceived of God (i.e. "the One", "Substance" or "the Absolute") as existing outside of time; for otherwise God's self-causation would become unintelligible.

On the other hand, however, quantum physics appears to upset this conclusion, because in quantum physics it does seem possible for causality to work backwards in time. I am, of course, referring to the mysterious retrocausality displayed in delayed choice experiments, where an act of observation can collapse the wave function of a quantum state not only in the present but also backwards in time, altering the state's past. This retrocausality, seemingly allowed by quantum physics, has been used by the theoretical physicist John Archibald Wheeler (1911-2008) to explain how reality has brought itself into existence. On Wheeler's hypothesis of the self-observing universe, present-day and future observers retro-actively collapse the wave function of the universe from the big bang onwards, thereby facilitating their own – as well as the universe's – evolution. On Wheeler's scenario, therefore, the self-causation of reality seems to be possible in time after all. In other words: Wheeler seems to contradict the claim that self-causation is only possible as a timeless process.

But is this really the case? In fact not, as I will show in the final section of this post. On Wheeler's account of the universe, time (at least as experienced by us ) becomes an illusion, and the self-causation of the universe turns out to be a timeless affair, a closed loop between past and future within the "block universe" which itself exists outside of time as a purely mathematical structure in 'Plato's Heaven'. Thus even on a Wheelerian approach to reality's self-causation, the latter remains a timeless process.

2. Time and the (im)possibility of self-causation
It seems prima facie clear that self-causation is impossible in time, and that the self-causation required to explain reality's existence must therefore be a timeless process. After all, on our normal, intuitive understanding of time and causality, only two kinds of temporal relation can obtain between a cause x and an effect y: either x is earlier than y, or x and y occur simultaneously. The latter happens in instantaneous causation, as when a locomotive starts pulling a train with perfect mechanical rigidity: the motion of the former instantaneously causes the motion of the latter. Instantaneous causation is a controversial concept, although some philosophers (notably Kant, Richard Taylor, Myles Brand) have reckoned with its possibility. Be that as it may, it is clear that the concept of self-causation is problematic in either case, both when x precedes y and when x and y occur simultaneously.

Kant thought instantaneous
causation was possible

Starting with the first case (the cause preceding the effect), it is clear that self-causation would require that the cause precedes in time its own existence, which would be absurd. The self-causing entity would literally have to travel back in time in order to effectuate its own existence. It seems we can safely dismiss this as impossible (pace quantum retrocausation). And the situation is not much better when we allow instantaneous causation in time. Admittedly, with instantaneous causation the self-causing entity would not have to travel back in time to cause itself, so in that sense the notion of self-causation becomes less problematic. Still, however, a lot of absurdity remains. For with instantaneous self-causation in time, there would first have to be a time when the self-causing entity did not yet exist, and then suddenly it would instantaneously cause itself to exist. Thus the self-causing entity would magically pop into existence out of nothing, like a 'hiccup from the void'. It seems clear that this fantastic scenario violates the principle that from nothing only nothing can come (ex nihilo nihil fit). Self-causation, then, seems impossible in time. But we need self-causation to explain reality's existence. Therefore we must postulate a timelessly existing self-causing cause of reality.

2.2 Platonic existence and the 'something-ness' of time
Some people argue that since self-causation is impossible in time, self-causation must be impossible per se. But then they falsely presuppose that all existence is temporal, thus forgetting two things. Firstly, they forget the possibility of Platonic existence: the non-spatiotemporal existence of ideal objects, paradigmatically mathematics. Thus the fact that self-causation is impossible in time leaves open the possibility that the self-causing cause of reality exists in 'Platonic Heaven' (and this raises the question whether the self-causation of reality could be mathematical in nature).

Secondly, they forget that time itself is something. Time – like space, with which it is intimately connected, as relativity shows – is an entity of sorts, a 'thing' with various properties (e.g. one-dimensionality, directedness, dilatability). Time, in other words, belongs to the 'something' we try to explain when we ask Leibniz's question: "Why is there something rather than nothing?" Since time obviously does not explain its own existence, it must be explained by something else, ultimately by the self-causing cause of all reality. But, as we have seen, self-causation is impossible in time. Thus time itself already presupposes timeless self-causation.

3. The issue of retrocausation in quantum physics
Above I argued that self-causation is "obviously" impossible in time, both in the case of instantaneous causation, where cause x and effect y occur simultaneously, and in the more normal case where x precedes y. But is this correct? How about retrocausality in quantum physics? There, apparently, an act of observation can collapse the wave function of a quantum state not only in the present but also backwards in time, altering the state's past. Doesn't this enable us to make sense of self-causation as a temporal process? The proposal of the self-observing universe, advanced by the physicist Wheeler, might be interpreted in this way. So does Wheeler give the lie to the claim that the self-causation of reality can only take place outside of time? I will finish this post with discussing this question.

John A. Wheeler (1911-2008)

Before discussing Wheeler's proposal in more detail, however, let us first become clearer about how quantum physics creates room for the notion of retrocausation. As already noted, in quantum physics it seems possible for an act of observation to collapse the wave function of a quantum state not only in the present but also backwards in time. That, at least, is what the famous delayed choice experiment seems to show. The delayed choice experiment was originally devised by Wheeler as a thought experiment in the late seventies and early eighties of the previous century, because back then the technology was not yet sufficient in order to realize this experiment in practice. Due to technological process, however, the experiment did become practically possible around 2006. The most rigorous version of the experiment was not done until 2007 by a research team led by French physicist Alain Aspect. The outcome of the experiment was surprising and precisely as originally predicted by Wheeler: observation is able to collapse wave functions in the past and thus to work retro-actively.

3.1 The delayed choice experiment
The delayed choice experiment can be understood as a variation on the classic double-slit experiment which demonstrates the particle / wave duality of quantum states and the curious involvement of the observer in determining which aspect of this duality comes to the fore. In the double-slit experiment, light from a point source falls on a screen with two slits in it; the light bounces off from the screen, except for the two slits through which some of the light passes, thus creating an image on a second screen. The image appears in the form of bright and dark vertical bands (interference fringes) which demonstrate the wave nature of light. The curious role of the observer in quantum mechanics then becomes manifest when the experimenter deliberately looks to see through which slit the photons pass, for in that case no interference pattern emerges and the wave-like nature of light is lost. The act of observation collapses the wave-function of the light and turns it into a stream of point-like particles.

The double-slit experiment

Thus far the double-slit experiment 'merely' demonstrates the wave / particle duality of light and the weird role of the observer in quantum mechanics. But it gets even weirder when the double-slit experiment is extended into a delayed choice experiment. Here the choice to observe through which slit the photons pass is delayed until the light has already passed through both slits and is just about to create an interference pattern on the second screen. Although the light has already passed unobserved through the slits, and therefore as a wave, the choice to observe nevertheless collapses the wave function and prevents the interference pattern from emerging. Again the act of observation has turned the light into a stream of point-like particles. But now a mystery arises: how is this possible given the fact that the light had already passed unobserved through both slits and therefore as a wave? That this is indeed the case follows from the fact that if the choice to observe had not been made, then the interference pattern would have emerged and the wave-like nature of light would have manifested itself. The only possible conclusion seems to be that the delayed choice to observe affects the nature of the light backwards in time, undoing its earlier wave-like nature and turning it into a stream of discrete particles!

3.2 But is this retrocausality?
To repeat: the light originally went through both slits as a wave, but the delayed choice then forced the light 'to change its mind' and 'retrace its steps', now no longer moving as a wave through both slits simultaneously but as a stream of discrete particles going through just one slit at a time. Let us also repeat the crucial point that this is not just quantum theory. The retro-active influence of observation on past quantum states has been demonstrated in real experiments. But is this retrocausality? This question is a hotly debated one. But the debate seems to be a largely verbal one, since it all depends on how you define "causality". In normal cases of causation, some information and energy is transferred from cause to effect. But no such transference takes place in the delayed choice experiments: from the collapse of the wave function in the past no information can be obtained about the future act of observation responsible for this collapse; likewise no energy is transferred from the future act of observation to the quantum state in the past. Thus it has been concluded that causality plays no role in the effect demonstrated by the delayed choice experiment.

But, as said, all this is to a large extent just semantics. Is the transfer of information / energy really essential to the concept of causation? Well, that's a matter of definition, isn't it? And therefore it is arbitrary up to a point. (Remember that the crisis of physicalism forces us to broaden our definition of causality anyway...) If we define "x causes y" broadly as x is the reason why y exists, as we did above in the introduction (a definition that seems reasonable), then clearly quantum physics allows retrocausation, since in the delayed choice experiment the present observation of a quantum state is the reason for the existence of its wave function collapse in the past. Thus, on a very broad definition of causation, quantum physics does allow retrocausation.

Wheeler's U diagram of
the self-observing universe

4. Wheeler's self-observing universe
But does this quantum retrocausation allow us to make sense of the self-causation of reality? The physicist Wheeler certainly thought so. He wanted to know how contemporary physics could explain the self-creation of reality. "How come existence?", Wheeler asked in his own truncated version of Leibniz's question (Wheeler 1999: 310). As we did above, Wheeler argued that, since there is nothing outside of reality as a whole, the latter must have a way of bringing itself into existence, through some kind of closed causal loop: "Existence is not a globe supported by an elephant, supported by a turtle, supported by yet another turtle, and so on. In other words, no infinite regress... To endlessness no alternative is evident but loop [...], such a loop as this: Physics gives rise to observer-participancy; observer-participancy gives rise to information; information gives rise to physics." (Idem: 313-4)

4.1 "How come the quantum?"
Wheeler looked in particular at quantum mechanics as allowing such a closed causal loop. In fact he explained the existence and nature of quantum reality ("How come the quantum?") by arguing that it is the universe's means for self-creation: "The strange necessity of the quantum as we see it everywhere in the scheme of physics comes from the requirement that – via observer-participancy – the Universe should have a way to come into being." (Wheeler 1983: 206) On Wheeler's account, then, the classical universe – i.e. the universe whose wave function has been collapsed – brings itself into existence by evolving the very observers whose acts of observation retro-actively collapse that wave function: "Beginning with the big bang, the universe expands and cools. After eons of dynamic development it gave rise to observership. Acts of observer-participancy ‒ via the mechanism of the delayed-choice experiment ‒ in turn gave tangible "reality" to the universe not only now but back to the beginning." (Wheeler 1983: 209) To illustrate this idea, Wheeler came up with the U diagram of the universe as "self-excited circuit": "Starting small (thin U at upper right), it grows (loop of U) and in time gives rise (upper left) to observer-participancy – which in turn imparts "tangible reality" [...] to even the earliest days of the universe." (Wheeler 1983: 209)

4.2 "It from Bit"
It should be stressed, however, that this appeal to quantum retrocausation on a cosmic scale forms only one half of Wheeler's hypothesis of the self-observing universe. As noted above, quantum retrocausation can only explain the classical universe, i.e. the universe whose wave function has been collapsed. This still leaves unexplained the universe at the quantum level, i.e. the universal wave function and the Schrödinger equation which describes its evolution. Where do they come from? If Wheeler's idea of the self-observing universe is to answer Leibniz's question, then Wheeler must also explain their existence. In order to do this, Wheeler left quantum theory behind and generalized his idea by making critical use of information theory. Wheeler argued – as one of the first – that physical reality ultimately consists of bits of information, a point of view encapsulated by his famous dictum "It from Bit". On this view, physical reality exists only for the observers who pose the yes-no questions to which the bits are the answers. As Wheeler puts it: "It from bit. Otherwise put, every it – every particle, every field of force, even the spacetime continuum itself – derives its function, its meaning, its very existence entirely – even if in some contexts indirectly – from the apparatus-elicited answers to yes or no questions, binary choices, bits." (Wheeler 1999: 310-11) Since the observers posing the yes-no questions are part of the very same information space that emerges through their questions, we should conclude that on Wheeler's account these observers ultimately bring themselves along with all of reality into existence.

Is reality nothing but information?

This is how Wheeler explains the existence of the universal wave function and the Schrödinger equation which describes its evolution: they emerge as special substructures in the information space created by the posers of the yes-no questions. Once the universal wave function exists in information space, and the evolution of its myriad superposed states is dictated by the Schrödinger equation, we find in one of its superposed branches the biological evolution of intelligent observers. These observers then retroactively collapse the universal wave function, resulting in their possible universe becoming the universe – the tangible, classical universe we observe around us. In this way concrete reality bootstraps itself into existence out of the abstract information space created by the observers who pose the yes-no questions – observers who, remember, are themselves part of that concrete reality.

On Wheeler's scenario, then, the universe must have emerged in such a way that conscious observers exist within it, since it is only in relation to them that the universe can exist. This also explains why according to Wheeler the information space contained the Schrödinger equation: because the latter facilitates the evolution of a universe containing intelligent observers. Wheeler pointed out that this is one way to explain the remarkable role played by the Anthropic Principle in cosmology. According to Wheeler, the bio-friendliness of the universe is just what one should expect for a participatory universe; he therefore spoke of the "Participatory Anthropic Principle" (PAP).

5. The timelessness of self-causation on Wheeler's scenario
Clearly Wheeler's hypothesis of the self-observing universe is indeed just that: a hypothesis – or rather, as Wheeler himself humbly admitted, an "idea for an idea". It is by no means yet a well-established scientific theory. This holds in particular for the information-theoretic side of Wheeler's hypothesis: the idea that posers of yes-no questions bring themselves into existence by creating the very information space in which they exist. This idea, clearly, is wildly speculative and incredibly vague. At least with the quantum-theoretical side of Wheeler's hypothesis we have some kind of theoretical and experimental underpinning (respectively, quantum mechanics and the delayed choice experiment). But even here we have no empirical evidence whatsoever for the claim that observers now and in the future retro-actively collapse the wave function of the universe all the way back to the big bang. Wheeler's hypothesis of the self-observing universe is therefore to a large extent pure speculation (as he himself was the first to admit). Nevertheless, the fact that this hypothesis presents a distinct scientific possibility, worthy of further investigation, is acknowledged by many contemporary philosophers and scientists. We should therefore take it seriously. So let us ask: is Wheeler's scenario at odds with the claim that self-causation is impossible in time?

5.1 The paradoxes of retrocausation as a temporal process
At first sight, this does seem to be the case, particularly in light of the quantum-theoretic side of Wheeler's scenario. As we have seen, Wheeler speculates that observers in the present and future retro-actively collapse the wave function of the past universe all the way back to the big bang, thereby facilitating their own and the classical universe's evolution. Thus the arrow of (self-)causation clearly points backwards in time. However, on closer inspection it becomes obvious that Wheeler does not describe the self-causation of the universe as a temporal process at all. Rather, on Wheeler's account, time – at least as experienced by us – becomes an illusion, and the self-causation of the universe turns out to be a timeless affair, a closed loop between past and future within the whole of spacetime which itself exists outside of time (the so-called "block universe"; see below). To see why this should be so, note first of all that the paradoxes surrounding self-causation as a temporal process still stand. On the intuitive conception of time (i.e. time as we experience it), only the present is fully real: the past exists no longer and the future exists not yet. On this intuitive conception, the only thing that fully exists is the "flowing now", this paradoxical limit which separates past from future and constantly moves forward, turning the future into the past. On this conception of time, self-causation by means of retrocausation is absurd: the self-causing entity would literally have to exist before it existed, it would have to travel backwards in time to cause its own existence. But how is this possible if only the present is real and both past and future are inexistent?

5.2 Retrocausation only possible in the "block universe"
In order for self-causation by means of retrocausation to be possible, therefore, this intuitive time must be an illusion. Only if past and future exist together does it make sense to see the future as having a causal effect on the past. That is: only if the "arrow of time" is an illusion (or at least a superficial phenomenon that does not characterize ultimate reality) is it possible for the arrow of causation to point in both directions, i.e. from the past to the future as well as from the future to the past. This "unreality of time" is a familiar view in physics, known as the "block universe". The block universe is a four-dimensional spacetime which represents all the places and all the times that ever have existed and will exist together as a single unchanging entity. There is no essential difference between the past and the future, because there is no present time defined to separate them; they cannot be distinguished from each other, so there is no meaningful present. 

Without an objective present, however, time cannot be said to flow in any real sense: the passage of time must be an illusion. The universe just is and contains the whole of spacetime. Only on such a picture of the universe, where past and future are equally real, is it possible for the future to have some kind of causal effect on the past. Only with a block universe, therefore, does retrocausation make sense. But as we have seen, the delayed choice experiment demonstrates the reality of a form of retrocausation (namely, a present observation collapsing a quantum states' wave function in the past). Thus we must conclude that the delayed choice experiment also demonstrates the unreality of intuitive time and the correctness of the block universe.  
 
5.3 The absence of time in the Wheeler-De Witt equation
That this is also Wheeler's own opinion becomes apparent when we take into account the fact that he is one of the co-inventers of the famous Wheeler-De Witt equation, which attempts to combine mathematically the ideas of quantum mechanics and general relativity. As is well-known, the parameter of time is conspicuously absent in general relativity. As such it constitutes the classic argument for the block universe. Since the Wheeler-De Witt equation attempts to combine general relativity with quantum mechanics, it imports this timelessness from general relativity into quantum theory. In a way, therefore, the Wheeler-De Witt equation is simply the universal wave function without the time parameter: it describes a timeless superposition of quantum states for the whole of spacetime. As such, the Wheeler-De Witt equation is one of the purest examples of the block universe in physics.

On Wheeler's account, then, the self-causation of the universe turns out to be a timeless affair, a closed loop between past and future within the block universe described by the Wheeler-De Witt equation. This timelessness of reality's self-causation, as conceived by Wheeler, is further confirmed by the information-theoretic side of his hypothesis of the self-observing universe. As we have seen, Wheeler speculates that reality starts of as an abstract information space created by the observers who pose the yes-no questions to which the bits are the answers – observers who are themselves inhabitants of that information space! But an information space is an abstract mathematical construct, existing timelessly in Plato's heaven. Thus, for Wheeler, the self-causation of reality comes down to a closed loop within a timeless mathematical structure.

References
-Wheeler, John A. (1983), "Law Without Law", in: J.A. Wheeler & W.H. Zurek (eds.), Quantum Theory and Measurement, pp. 182-213. Princeton University Press.
-Wheeler, John A. (1990), "Information, physics, quantum: The search for links", in: W.H. Zurek (ed), Complexity, Entropy, and the Physics of Information. Redwood City, California: Addison-Wesley.

Dialectical Nihilism: An Essay on Nothing (and its Structure)

For a printable version of this text see: Dialectical Nihilism: An Essay on Nothing (and its Structure)

"If you look at zero you see nothing;
but look through it and you will see the world."
(Robert Kaplan)

"We are such stuff as dreams are made on;
and our little life is rounded with a sleep."
(Shakespeare)

"0 is the egg
reality is the hatchling
positive and negative
are its wings

fluttering about
without purpose or design
finding nourishment
where it can

till late at night
when it goes to sleep
it folds its wings
and becomes zero again"
(Me)


Introduction: My painful black ToE
The last few weeks I have been toying with a crazy theory that I like to call "dialectical nihilism". I am, in fact, deeply ambivalent about it, unable to decide whether it is just plain crazy or rather the best ToE (Theory of Everything) out there. I like to call it "my painful black ToE" because its ultimate explanation of everything is the total 'blackness' of absolute nothingness. The fact that there nevertheless appears to be something is then explained by the hypothesis that this nothingness is not without structure: it is composed of infinitely many antithetical elements (or polar opposites) that cancel each other out and thus add up to nothing. Obviously, this focus on the mutual cancellation (or "Aufhebung" as Hegel would say) of polar opposites explains one of the senses in which dialectical nihilism is dialectical. In fact, as I intend to show in the following, dialectical nihilism is dialectical in four senses in that it facilitates:

(a) a dialectical reversal of everything (that exists) into nothing;
(b) a dialectical conception of the nothing as composed of polar opposites;
(c) a dialectical "logic of illusion" (Kant) that unmasks the illusory nature of existence under the principle of sufficient reason;
(d) a dialectical reversal of negative into positive nihilism, i.e. the reversal of the negation of life as absurd and meaningless into an affirmation of life as a groundless and wonderful gift.

In the following I will explain dialectical nihilism more fully, developing – in a rough-and-ready form – its main theses and the various arguments in favor of it. I should stress, however, that although the term "dialectical nihilism" is my own invention, most of the ideas behind it are not original and have been around since the times of Anaximander, Heraclitus, Laozi and Buddha. Moreover, in recent years the dialectical conception of nothingness as composed of polar opposites has regained a lot of interest due to the emergence of the (in)famous hypothesis of the zero energy universe in physics. The basic idea behind this hypothesis is that since the universe is composed of equal amounts of positive and negative energy – amounts that cancel each other out – the universe as a whole contains no energy at all. In this way the universe appears to be strangely empty, especially if you consider the fact that matter is a form of energy as well. According to many physicists – ranging from Alan Guth and Stephen Hawking to quantum chemist Peter Atkins – the hypothesis of the zero energy universe explains how the universe could have emerged from nothing, namely, through a kind of 'splitting' of nothing into positive and negative energy. The biochemist and popular science(-fiction) writer Isaac Asimov appears to have been very prescient in this regard, already writing about this in 1974:  

"Where did the substance of the universe come from?... If 0 equals ( + 1) + (-1), then something which is 0 might just as well become + 1 and -1. Perhaps in an infinite sea of nothingness, globs of positive and negative energy in equal-sized pairs are constantly forming, and after passing through evolutionary changes, combining once more and vanishing. We are in one of these globs between nothing and nothing and wondering about it." (Asimov 1974: 69-70)

Sunyata, the Buddhist concept of emptiness

Dialectical nihilism latches on that idea but gives it a Buddhist twist. If the universe is really composed of polar opposites that cancel each other out and thus add up to nothing, then in what sense can the universe be said to exist at all? If the universe is just an empirical manifestation of nothingness, doesn't this imply that the existence of the universe is illusory? Hence the nihilistic aspect of dialectical nihilism. But, as I suggested above, this nihilism is dialectical also in the sense that it enables a reversal from negative to positive nihilism. I find the idea of dialectical nihilism strangely liberating in that it allows you to return to daily life with less attachment and thus also with less sorrow, since – as the Buddha said – desire is the root of all suffering. At the same time it allows you to return to life with a fresh sense of (aesthetic) wonder about this infinitely complex tapestry of appearances we call reality – appearances in which ultimately nothing appears and where "the rose flowers without why" as the 17th century mystic Angelus Silesius so aptly put it. In this way dialectical nihilism can be said to bring about existential illumination or Enlightenment if you will. But paradoxically the light that illuminates the whole coincides with the absolute darkness in which the whole dissolves.

Dialectical nihilism: The basic idea
The basic idea behind dialectical nihilism is that existence is really nothing (i.e. in reality nothing exists) but that this nothing consists of infinitely many antithetical elements (or polar opposites) that cancel each other out and thus add up to nothing, like -1+1=0 or equal amounts of positive and negative energy adding up to no energy at all. Thus these antithetical elements (or "beings and antibeings" as I like to call them) do not really exist, they have "always already" cancelled each other. Yet as cancelled they are nevertheless still contained in the nothing to which they add up. Following Hegelian dialectics we could say that all possible beings and antibeings are Aufgehoben (sublated) in the nothing, where "Aufhebung" carries the double meaning of elimination and sublimation (or conservation on a higher level). The difference with Hegelian dialectics is that whereas for Hegel Aufhebung is always the result of a logical-temporal process (the march of Spirit through world history), for dialectical nihilism it is a static state of affairs outside of time. Indeed, it is the empty state of affairs, where nothing at all exists. The whole of reality just is this Aufhebung that has always already taken place, i.e. the nothing that contains in sublated form all possible beings and antibeings.

To repeat: as cancelled, these beings and antibeings do not exist. They are no more than possibilities (potentialities, virtualities) within the nothing. Here dialectical nihilism relies on an ancient and perhaps also commonsensical idea, namely, that in a state where nothing exists everything is still possible. The idea is plausible on an intuitive level: when you have a block of marble still untouched by a sculptor, all forms are still possible within it, but once the sculptor starts shaping it, actualizing one of its possible forms, all the other forms thereby become impossible. Now for dialectical nihilism, the nothing is like an infinite block of pristine black marble in which all forms are possible. There is only one limitation on these forms: they must be such that together they form this black marble of nothingness. Hence the stress on antithetical elements, because these cancel each other out. So everything is possible in the nothing as long it is composed of antithetical elements that add up to nothing. Thus, paradoxically, everything is possible as long as it is impossible, i.e. self-cancelling.

The presocratic philosopher Anaximander
already theorized that all things emerge
through a splitting of the void (apeiron)
into polar opposites.

So how do we get from there – where nothing at all exists – to here, our reality, where there nevertheless appear to exist a great many things, from quarks and quasars to headaches, the number pi, cheese sandwiches and beautiful women? According to dialectical nihilism, the keyword here is "appear": there appear to be many things, including ourselves. And "appearance" can also mean "mere appearance", "illusion". That things appear to exist doesn't mean they actually exist. In fact, according to dialectical nihilism, they don't exist: all beings 'are' no more than mere appearances, illusions, the "veil of Maya" as the Buddhists say. There 'are' appearances but there is nothing that appears in them. They are literally appearances of nothing. In Kantian terminology we could say that nothingness is the thing-in-itself behind (or beneath) the phenomenal world (thus, to paraphrase Kant, we have empirical realism but transcendental nihilism).

But, so we might ask, can't we then at least say that these appearances exist? Isn't illusion, however illusory, still something and not nothing? Doesn't the claim that there are only appearances contradict the other claim that nothing exists? In the following I will try to answer this objection in a systematic way. I will try to show that if we conceive of the nothing as composed of all possible beings and antibeings, then we with our illusory existence must be there enveloped in the nothing as well. We with all our experiences are also just unactualized possibilities within the nothing; hence the illusory nature of those experiences. For now, however, it suffices to say that the mode of existence of appearance/illusion is deeply problematic anyway.

The sensory flux according to Van Gogh

Already the ancient Greek and Indian philosophers recognized that if appearance can be said to exist at all, then that existence is deeply paradoxical and bordering on non-existence. One problem, of course, lies in the temporal, fleeting, transient nature of the phenomenal world. When we consider what appears closely, we find that it is never the same, it continuously changes in a never-ending sensory stream. As Plato said: "All is flux, nothing stays still." But if it is never the same, if it never endures, if it always becomes, how then can it ever be said to be? We can say "appearance exists", but if we can't say what exists – since there is no what, no remaining essence or identity – then the existence of appearance becomes very thin indeed. Hence Plato saw the sensory flux as a kind of non-being. Of course, Plato was still able to discern real enduring being behind the flux in the form of the eternal Ideas, whose timeless existence was guaranteed by the "light of intelligibility" radiated by the highest Idea, the Good. But, as we might say, such Platonism has become obsolete for us (post-)moderns who "don't believe in nothing no more". Indeed, for dialectical nihilism, nothing exists behind the veil of appearances, nothing but absolute nothingness itself. 

The reasons for dialectical nihilism
Up till now I have merely been explicating the idea of dialectical nihilism. But what are the reasons for it? Why believe in such a crazy theory at all (indeed, I ask myself this all the time). Well, believe it or not, there are actually good reasons for it. We have already mentioned one: the problematic 'existence' of the phenomenal world, the sensory flux. Of course, this doesn't yet justify the conclusion that nothing at all exists nor that this nothing is the ultimate Aufhebung, the coincidentia oppositorum of all possible beings and antibeings. To establish these conclusions other arguments are needed. In the following I will discuss two such arguments. First I will discuss some contemporary physics and focus on the role played by polarities in physical reality, polarities which are such that they cancel each other out, thus making the universe look strangely empty (fermionic polarity and the hypothesis of the zero universe). Then I will discuss the problematic nature of the concept of existence, which becomes apparent when one tries to answer Leibniz's famous question "Why is there something rather than nothing?". The logical impossibility of explaining why there is anything at all undermines the very idea that there is anything at all. Thereafter I will discuss the nature of absolute appearance and attempt an explanation – on the basis of the idea that nothingness is composed of antithetical elements – why there appears to be something. Finally I will finish up discussing some theories that look like dialectical nihilism but in fact aren't (negative theology, the informational theory of nothing) and by spelling out some of the more spiritual aspects of dialectical nihilism, its closeness to Buddhism, Daoism and all that.

The possibility of empirical evidence for dialectical nihilism
In discussing the empirical evidence for dialectical nihilism, we should beware not to shoot ourselves in the foot. After all, we have just declared the empirical world to be an illusion. How then can empirical evidence have any value for us? I think, however, there is a way out of this conundrum. Remember our earlier Kantian claim that nothingness is the thing-in-itself behind the phenomena. In the same vein we said that in the appearances there is nothing that appears. My suggestion now is to take this literally: what appears is the nothing, such that it makes itself apparent in the appearances. Thus, if the nothing is the coincidentia oppositorum, then this antithetical structure of the nothing will become apparent in the phenomena. On could compare this to a doctrine in Schopenhauer's philosophy with which dialectical nihilism has indeed many things in common (see below on the principle of sufficient reason and illusory nature of empirical reality). As is well-known, Schopenhauer took the Kantian thing-in-itself to be an antagonistic, internally divided Will-to-Life. Thus the bellum omnium contra omnes that according to Schopenhauer characterizes our empirical world is interpreted by him as expressing on the phenomenal level the antagonistic nature of thing-in-itself, the Will-to-Life. I suggest that something similar holds for dialectical nihilism, save that here of course the thing-in-itself is not rethought as Will-to-Life but as antithetically structured nothingness. Thus the phenomenal world comes to express this antithetical structure.

One further way to understand this is in terms of what I said above about the nature of possibility: everything is possible within the nothing as long as it is impossible, i.e. as long as it is composed of antithetical elements that add up to nothing. Thus, we can say, the empirical world studied by physics is possible only if it is ultimately nothing, i.e. only of it is composed of polar opposites that cancel each other out. In this way the empirical world expresses – in a Schopenhauerian sense – the antithetical structure of the nothing. In this very general sense, one could say, dialectical nihilism makes an empirical prediction, namely, that the empirical world is composed of mutually cancelling polar opposites. And surprisingly, this prediction is confirmed by contemporary physics as it shows how the physical universe is characterized on a fundamental level by various polarities, notably the polarity between matter and antimatter, and between positive and negative energy. Now, according to many physicists, these polar opposites ultimately cancel each other out, thus adding up to nothing. According to them, this is precisely what allows us to explain how the universe could have emerged from nothing, i.e. why the Big Bang occurred, namely, because nothing somehow 'split' itself into positive and negative energy, and into matter and antimatter! Clearly, this scientific theory – which is advocated by many renowned physicists like Alan Guth, Ed Tryon, Stephen Hawking and Lawrence Krauss – fits dialectical nihilism hand in glove.

Yet there remains a big difference: physics obviously operates under the assumption that physical reality is real, that it exists, whereas dialectical nihilism claims that the existence of physical reality is illusory since ultimately nothing exists. Or, to anticipate conclusions from following paragraphs, physics operates under the principle of sufficient reason (PSR), the assumption that physical reality can be fully explained in terms of fundamental causes, whereas dialectical nihilism – following Kant and Schopenhauer – stresses the logical incoherence of applying the PSR to the universe (or everything that exists) as a whole. Thus there is no ultimate explanation of the universe; the chain of causes stretches back to infinity, both spatially (the infinitely small) and temporally (the infinite past), and the entire causal chain becomes curiously free-floating, suspended in mid-air so to speak, which shows precisely its illusory nature. Physics, working under the assumption of the PSR, can think of the relation of the universe to the nothing only as a temporal and causational relation, such that the universe emerges out of nothing, with the latter acting as a kind of first cause of the universe (the 'splitting' of nothingness into positive and negative energy). For dialectical nihilism, however, this is ultimately an incoherent notion, partly because the temporal chain of causes is necessarily infinite and thus without a first cause, and partly because the idea that nothingness can cause anything simply makes no sense (a cause must be something that exist, but the nothing is precisely the inexistent, so how then could it possible cause anything?). The temporal origination of the universe out of nothing, therefore, is for dialectical nihilism part of the illusory appearance of the nothing. In other words: within the empirical world, the nothing appears as the first cause in time, but in truth the entire temporal chain of causes (i.e. the empirical world as a whole) is an illusory appearance of the nothing within the nothing.

Perhaps we can make this more precise in mathematical terms by considering the fact that zero is the precise sum of all positive and negative numbers. You can picture this sum as a folding of the real number line onto itself using zero as the hinge, so that every number on that line meets its negative counterpart: in that way all numbers are subtracted and only zero remains. Now what if zero, as the sum of all numbers, can be said to still contain all those numbers within itself in a sublated, cancelled form, as pure unactualized possibilities? In that sense one could say that zero is the ultimate coincidentia oppositorum in mathematical form, and the above idea that the nothing consists of all possible beings and antibeings gains a clear (or perhaps not so clear) mathematical sense. Add to this the idea that physical reality can ultimately only be known through numbers (the fundamental formulae of physics), and the conception of our universe as a possible configuration within the nothingness of zero becomes a distinct even if speculative possibility on the horizon of science. But for now I must leave this – admittedly very speculative – suggestion undeveloped.

The hypothesis of the zero energy universe in physics
To repeat: contemporary physics confirms dialectical nihilism in that it pictures the universe as basically nothing, because the polar opposites that compose it cancel each other out. This, according to many physicists, is what allows the universe to have emerged from nothing without violating the common sense principle that from nothing only nothing can come. In physics, of course, this principle is known as the law of energy conservation: energy (or its equivalent in mass) can neither be created out of nothing nor destroyed. Given this law, the only way for the universe to have emerged out of nothing is if it actually consists of zero energy, which in turn is only possible if the positive and negative energies in the universe cancel each other completely. As Hawking and Mlodinow put it: "Bodies such as stars or black holes cannot just appear out of nothing. But a whole universe can... On the scale of the entire universe, the positive energy of the matter can be balanced by the negative gravitational energy, and so there is no restriction on the creation of whole universes." (Hawking and Mlodinow 2010: 227) This obviously requires some further explanation. Let’s start with the concept of positive energy. This is the energy invested in matter, both in the constitution of matter itself ('congealed energy') and in its movement (kinetic energy). Obviously, given the sheer size of the material universe, there is a tremendous lot of positive energy (though no one is quite sure how much). At the same time, there appears to be an equal amount of negative energy stored in the gravitational attraction that exists between all pieces of matter. The positive energy of matter is therefore precisely balanced by the negative energy of gravity, so ultimately there is no energy in the universe at all. Here is how Stephen Hawking explains it:

"[T]he total energy of the universe is exactly zero. The matter in the universe is made out of positive energy. However, the matter is all attracting itself by gravity. Two pieces of matter that are close to each other have less energy than the same two pieces a long way apart, because you have to expand energy to separate them against the gravitational force that is pulling them together. Thus, in a sense, the gravitational field has negative energy. In the case of a universe that is approximately uniform in space, one can show that this negative gravitational energy exactly cancels the positive energy represented by matter. So the total energy of the universe is zero." (Hawking 1988: 146)

This is a crucial conclusion. Since everything in the physical universe is in one form or another made of energy, the fact that that energy is zero implies that in physical terms there exists nothing at all! As we have noted, this greatly simplifies the task of explaining how the universe came into existence. Since, energetically speaking, the universe is nothing, its ultimate cause can be nothing. The well-known quantum chemist Peter Atkins puts this point as follows: "First, it is important to realize that there probably isn’t anything here anyway… Of course we are part of and surrounded by things; but at a deep level there is nothing. I shall now try to resolve this paradox, for once it is resolved the notion of creation ex nihilo – creation of something from absolutely nothing – is greatly simplified… The bottom line, prejudiced with a dash of speculation, is that the initial endowment of energy at the creation was exactly zero, and the total energy has remained fixed at that value for all time… What we see around us is in fact nothing, but Nothing that has been separated into opposites to give, thereby, the appearance of something..." (Atkins 2011: 13, 17)

Fermionic polarities and quantum fluctuations
In physics this idea – that reality emerged out of nothing because the nothing split into polar opposites – can be found on two levels, firstly in the theory of how matter and antimatter emerge from quantum fluctuations, secondly in the theory of cosmic inflation which tells how positive and negative energy became separated during and immediately after the Big Bang. In the following we will take a short look at both theories. Let's start with the polarity of matter and antimatter. Since matter consists of particles, this polarity comes down to an opposition between particles and antiparticles (collectively known as "fermions"). According to quantum physics, for every type of particle there is a type of antiparticle with opposite properties, such that when they meet they annihilate each other. In fact, particles and antiparticles can only come into existence together, in pairs. Here is what John Gribbin writes about it: "The only way you can make a 'new' fermion, such as an electron, out of energy is if, at the same time, you make a mirror-image anti-particle (in this case, a positron). The mirror-image particle has opposite quantum properties (including, in this case, positive electric charge instead of negative electric charge) so the two cancel each other out for the purpose of counting fermions, with one negative and one positive adding up to nothing." (17) Thus "when a positron meets an electron, both particles disappear in a puff of high-energy photons – gamma rays – as their opposite quantum properties cancel each other out." (Gribbin 2007: 62)

Electromagnetic polarity is a prime example of fermionic polarity. Positrons have positive electric charge, they repel each other but attract the electrons which have negative charge. Since there is a negative charge for every positive charge, all the charges ultimately cancel each other, so in the final analysis the total electric charge of the universe is precisely zero. It is important to remember, however, that electromagnetic polarity is only one example of fermionic polarity. Even the particles with no electric charge have this fundamental property of being paired to a type of antiparticle. There is an antimatter counterpart for the neutron, for example, even though these particles lack electric charge.

As noted above, particles and antiparticles can only be created together, in pairs. Since a particle and its antiparticle add up to nothing, the crucial question is whether they can also emerge from nothing. In fact, quantum physics reveals that something like this does actually happen. This is the so-called quantum fluctuation of the false vacuum, whereby particle-antiparticle pairs (such as electrons and positrons) spontaneously pop in and out of existence in empty space. In quantum mechanics, this is partly explained by Heisenberg’s uncertainty principle, which – among many other things – says you cannot precisely measure both the value of an energy field and the rate at which it changes. Knowledge of the one implies uncertainty about the other. This pretty much rules out the possibility of empty space, which by definition is a state with zero energy. But Heisenberg’s principle tells us that if the value of a field is precisely known to be zero, its rate of change is completely random and thus can’t be zero. So even in ‘empty’ space, the energy level fluctuates randomly. Thus the vacuum is better described as a false vacuum, since strictly speaking a real vacuum is impossible, ruled out by the uncertainty principle. In reality, therefore, 'empty space' is seething with activity on the quantum scale, with particle-antiparticle pairs popping in and out of existence all the time.

The separation of positive and negative energy in inflation
So here we have one way in which physics countenances the idea of nothing splitting into opposites, namely, into matter and antimatter. However, we are actually cheating a bit here because the particle-antiparticle pairs do not literally emerge out of nothing. Rather they emerge out of the fluctuating energy level of empty space, which may seem rather ephemeral, but it definitely is not absolutely nothing. So where does the false vacuum come from? Why is there the energy of empty space to begin with? This is where the theory of cosmic inflation comes in. This theory is originally due to physicist Alan Guth, who suggested that the early universe during the Big Bang went through a period of extremely rapid exponential expansion. According to Guth, the radius of the universe increased by a million million million million million (1 with eighty zeros after it) times in only a fraction of a second. This involved a process of repeated doubling of the universe's size; hence the exponential nature of the growth. Thus the inflationary theory explains why the expanded space of the current universe is there, how it evolved from an infinitesimally small point (called the singularity). We are not going to discuss the details of the inflationary theory here, since that would take us too far afield. What should be noted, however, is that the inflationary theory involves a weird interplay of positive and negative energy, a seemingly magical process in which these two opposite forms of energy emerge out of nothing by becoming separate.

The theory of cosmic inflation was first
developed in the 1980s by physicist Alan Guth.

One way to understand this is through Einstein's discovery that space and gravity are intrinsically linked. On Einstein's general theory of relativity, gravity just is the curvature of space. But we have also seen how gravity represents negative energy as opposed to the positive energy represented by matter. The process of the inflationary expansion of space, therefore, can also be seen as a process in which the negative energy of gravity increased exponentially. But how is this possible, given the law of energy conservation, according to which energy cannot be created or destroyed? As we have already seen, free creation of energy is only possible because of the mutual cancellation of positive and negative energy. One form of energy can increase arbitrarily only so long as the opposite form of energy increases with the same amount, so that the total amount of energy remains constant. This is precisely what happened during inflation: the exponential increase of the negative energy of gravity/space went hand in hand with an equal increase of positive energy. Out of this positive energy then emerged matter and antimatter through quantum fluctuations. Thus, as Hawking writes about the inflation process: "when the universe doubles in size, the positive matter energy and the negative gravitational energy both double, so the total energy remains zero. During the inflationary phase, the universe increases its size by a large amount. Thus the total amount of energy available to make particles becomes very large." (Hawking 1988: 147)

The process of inflation, then, involved a separation of positive and negative energy. The physicist Tegmark (2014: 105) describes this as a kind of "release": the exponentially increasing negative energy of inflating space "released" an equal amount of positive energy. But this metaphor of release is misleading insofar as it suggests that negative energy came before positive energy, as if the increase of the first caused the increase of the latter. The truth is that, according to inflationary theory, positive and negative energy emerged simultaneously as they separated out of a state of zero energy. Insofar as talk of release is at all appropriate here, we should rather say that it was the state of zero energy which released both negative energy (gravity/space) and positive energy (the source of matter) out of itself. Alan Guth was well aware of this strange aspect of his theory, which seems to show how the universe can emerge out of nothing. Hence his famous remark that the universe is "the ultimate free lunch".

The problem of initial conditions in physics
In sum, dialectical nihilism is confirmed by physics on two counts. Firstly with regard to the idea that reality is basically a form nothing; this is confirmed by the hypothesis of the zero energy universe, where the amounts of positive and negative energy cancel each other out. Secondly with regard to the idea that reality exists because the nothing split itself into polar opposites; this is confirmed by the spontaneous creation of particle-antiparticle pairs out of quantum fluctuations, and by the inflationary theory according to which positive and negative energy separated out of an initial state of zero energy. Of course, according to dialectical nihilism, there has been no real temporal origination of the universe out of nothing: the appearance of such a temporal origination is part of the illusion of existence due to the antithetical structure of nothing. Because of the regressive nature of the PSR, the temporal chain of causes is infinite, ruling out a first cause for the universe.

The problem of causal
regress: "it's turtles
all theway down".

In physics this problem is reflected in the difficulty of finding the initial conditions of the universe. The universe is said to have emerged from a Big Bang, but what were the initial conditions that caused the Big Bang? And what in turn caused those initial conditions? Obviously there is a regress here that precludes the possibility of ever finding an ultimate explanation for the temporal emergence of the universe. Thus physicists disagree about which was primary: did a primordial quantum fluctuation first gave rise to the singularity which was then 'blown up' by cosmic inflation (as argued by physicists like Page, Filippenko and Pasachoff), or did inflation come first, producing the empty space needed for quantum fluctuations to occur in (as argued by Guth, Hawking and Krauss)? (I have dealt with the problem of initial conditions in physics more fully in this paper.) According to dialectical nihilism, this problem is insoluble within physics, simply because there can be no first cause of the universe due to the regressive nature of the PSR. Indeed, as I will argue in the following paragraph, the regressive nature of the PSR undermines the very assumption that "existence" is a logically coherent notion.

The illusory nature of existence under the PSR
Once you start to think about Leibniz's famous question – "Why is there something rather than nothing?" – you notice that there is something fishy about it. What could possibly be the reason or cause why anything exists? Wouldn't that reason/cause itself have to involve something that exists, since ex nihilo nihil fit, from nothing only nothing comes? But if we already have to presuppose the existence of something to explain why anything at all exists, then clearly existence as such cannot be explained. And if it can't be explained, if we can give no reasons why anything exists, then how can we be so sure that anything exists at all? How can we exclude the possibility that existence is just an illusion? In fact, my contention is that when we think systematically about this issue, we cannot avoid the conclusion that the very idea of existence is fraught with paradox and must therefore be rejected – in other words: the only valid conclusion is that "nothing exists". I think this follows if we accept the following axioms, which in themselves appear to be straightforward and commonsensical: 

Leibniz (1646-1716) was a true
innovator: among his many con-
tributions are the PSR and the
first formulation of the question
"Why is there something
rather than notthing?"

(A1) There appear (to be) beings. A being is anything that exists. If something does not exist (i.e. is not a being), then it is nothing.
(A2) All beings fall under the principle of sufficient reason (PSR), such that for every being there is a sufficient reason explaining why it exists and why it is the way it is. The reason that explains a being must itself also be a being, i.e. something that exists. No being can be its own reason.

Now, to begin with, it follows from (A1) and (A2) that there can be no totality of beings, i.e. that that totality is nothing. This can be shown by way of a reductio ad absurdum: Suppose a contrario that there does exist a totality of beings. In that case – because of (A1) – the totality would itself also have to be a being, which – because of (A2) – would fall under the PSR. But then there would have to be another being outside of the totality of beings (since no being can explain itself), which is contradictory, since by definition nothing exists outside of that totality. Thus the totality of beings cannot possibly fall under the PSR and it cannot possibly be a being, hence it must be nothing. And if there is no totality of beings, then there simply are no beings whatsoever!

But doesn't this contradict (A1)? No, because (A1) merely says: there appear (to be) beings. Beings appear to exist, but – given the above argument – they don't really exist. In truth, nothing exists. Beings are therefore merely appearances, illusions. To clarify this crazy conclusion, note that it can also be argued for in the following way:

From (A2) it follows that a being exists only if there is a sufficient reason for it, i.e. a second being that explains it. But then this second being also needs a sufficient reason to exist, i.e. a third being which in turn requires a fourth being and so forth ad infinitum. Thus there is a regressive aspect to the PSR, as is of course well-known. Once you accept the PSR, you are on a potentially infinite regress of beings explaining beings – a regress that can only be stopped by assuming there is an ultimate being that explains itself, a 'God' whose essence implies his existence. This traditional solution, however, is ruled out by (A2) which says that no being can be its own reason. It is, after all, easy to see that the notion of a self-grounding being is logically incoherent. For one, such a being would have to exist before it existed. If it didn't already exist, how could it possibly explain anything else (including itself)? So this solution to the regress problem is blocked. The regress implied by the PSR is therefore infinite. And this means that ultimately no being is explained by any other being, since there is no ultimate reason (explanation, cause) that grounds everything else. And since – because of (A2) – a being can only exist if there is a sufficient reason for it, this means that no beings at all exist. The causal chain of beings, because it is potentially infinite, remains curiously free-floating, ungrounded, suspended in mid-air. In that sense the entire causal chain is illusory. Of course, we see things around us, or as we said in (A1): there appear to be beings. But nowhere are these appearances grounded in something that really exists. They are mere illusions.

This analysis of the illusory nature of existence under the PSR brings dialectical nihilism in the vicinity of Kant's dialectic qua "logic of illusion". In the second part of his Critique of Pure Reason, Kant develops a "transcendental dialectic" by showing how human reason entangles itself in illusions and antinomies by tracing the conditions of the empirical world back to the ultimate conditions or unconditioned. Basically he develops the aporiae of ultimate explanation under the PSR as we have done above. His details may differ from our account, but the gist is the same. The Kantian meaning of "dialectic" as "logic of illusion" is therefore one of the aspects of dialectical nihilism.

The PSR in Buddhism and Schopenhauer
In Mahāyāna Buddhism this conclusion – the illusory nature of existence under the PSR – is known as the emptiness ("sunyata") of the world due to its dependent origination ("pratītyasamutpāda"). The doctrine of dependent origination is the Buddhist version of the PSR: it says that all beings arise only in dependence upon prior conditions. Seeing that this dependence never terminates, that there is no ultimate condition that grounds the totality of beings, Buddhism concludes that all beings are empty of intrinsic existence. The world of dependent origination – where, as the Buddha said, "this is only because that is" – is ultimately unreal, an endless web of illusions, "the veil of Maya". The philosopher Graham Priest explains the Buddhist notion of emptiness on the basis of dependent origination as follows:

"The existence of any thing is constituted by, and only by, the existence of other things, whose existence is constituted by, and only by, the existence of other things, and so on. Since there is nothing that grounds this process, there is nothing that ultimately constitutes the existence of anything. Nothing, therefore, exists." (Priest 2009: 471)

In Western philosophy the same conclusion was drawn by Schopenhauer on the basis of his reflections on the PSR. Of course, Schopenhauer was in this regard strongly influenced by Buddhism, but he also points to classic thinkers in the Western tradition as anticipating the same conclusion (see the quote below). For Schopenhauer, the emptiness of the world under the PSR is most clearly demonstrated by the paradoxical nature of time, where each moment follows from the preceding one, thus showing the PSR in its most simple form:

"This simplest form of the principle [of sufficient reason] we have found to be time. In it each instant is only in so far as it has effaced the preceding one, its generator, to be itself in turn as quickly effaced. The past and the future [...] are empty as a dream, and the present is only the indivisible and unenduring boundary between them. And in all the other forms of the principle of sufficient reason, we shall find the same emptiness, and shall see that not only time but also space, and the whole content of both of them, i.e., all that proceeds from causes and motives, has a merely relative existence, is only through and for another like itself, i.e., not enduring. The substance of this doctrine is old: it appears in Heraclitus when he laments the eternal flux of things; in Plato when he degrades the object as that which is ever becoming but never is; in Spinoza as the doctrine of the mere accidents of the one substance which is and endures. Kant opposes what is thus known as the mere phenomenon to the thing in itself. Lastly, the ancient wisdom of the Indian philosophers declares, "It is Maya, the veil of deception, which blinds the eyes of mortals, and makes them behold a world of which they cannot say either that it is or that it is not: for it is like a dream; it is like the sunshine on the sand which the traveler takes from afar for water, or the stray piece of rope he mistakes for a snake."" (Schopenhauer 1958: 7-8)

The inexistence of absolute illusion
So, to summarize, from (A1) and (A2) we derive the nothingness of the totality of beings and the concomitant conclusion that all beings are nothing more than empty appearances, illusions. Now, however, one might ask whether these two conclusions contradict each other. After all, if in truth nothing exists, how then can there be appearance at all? Isn't even appearance, no matter how illusory, still something that exists and thus not nothing? Yet this existence of illusion/appearance is very hard to make sense of. We have already pointed to the fleeting nature of the sensory flux as something that undermines the existence of appearance. We can now fortify this conclusion in the following way: insofar as illusion exists, it must – because of (A2) – fall under the PRS and as such it becomes part of the very same vicious regress that undermines the notion of real existence. So the only thing we can say, if we insist that illusion too exists, is that there appears to be illusion, or that we are under the illusion that there is illusion. And if this illusion of illusion is in turn something that exists, then we simply get an illusion of illusion of illusion. Clearly, as long as we take appearance/illusion as something that exists, we get an infinite regress similar to the regress of beings under the PSR – i.e. we get an illusory appearance that there is an illusory appearance and so on. Nowhere does this regress terminate in real being, nowhere can the naked existence of illusion be pinpointed. The existence of illusion slips through our fingers whenever we try to grasp it. But, so one might ask, can't we then say that at least this infinite regress of illusions exists? It shall be clear by now that all we can say is that there appears to be this regress of appearances. Such is the nature of absolute illusion, which is so all-encompassing that even its own existence is illusory. Thus our conclusion that nothing at all exists does not contradict our second conclusion that there are illusions/appearances.

Impossible to see the whole

Explaining the illusion of existence
Nevertheless, we still have the feeling that we must explain something, however hard this 'something' might be to define. We still want to know why – given the conclusion that nothing at all exists – there nevertheless is (or appears to be) the illusion of existence. As I indicated in the Introduction, dialectical nihilism explains this illusion in terms of a dialectical conception of the nothing as consisting of infinitely many antithetical elements that cancel each other out. Thus in truth nothing at all exists, but this nothing consists of infinitely many possible beings and antibeings. These beings and antibeings do not exist. They are merely 'present' or 'contained' in the nothing in a sublated, annihilated, canceled form. As we will say: they inexist in the nothing, where "inexist" carries the double meaning of "inexistence" and "existing in". The nothing is the totality of all possible mutually cancelling, inexisting beings and antibeings. Now the fact that for us there nevertheless appear to exist beings follows from our finitude as observers, which keeps us from seeing the whole, the nothing. As finite, limited observers we see only fragments of the whole, not the whole itself, and these fragments necessarily appear to exist, simply because we abstract them away from the whole in which they are nothing. It is because we as finite observers have only a partial view on the whole that beings appear to us. Were we to see the whole we would see nothing, because then we would see all beings as cancelled by their antibeings. It is precisely because we are imperfect that we see something. For a perfect mind, there simply is nothing to see. It would see the whole, the ultimate coincidentia oppositorum and thus nothing at all. Indeed, such a perfect mind would see its own non-existence as well: as soon as it sees the whole it becomes one with it, thereby disappearing altogether.

Now it might be said there is an obvious objection to this story. According to the above explanation, the illusion arises because we as finite observers see only a fragment of the totality of all possible beings and antibeings that together add up to the nothing, and that fragment necessarily appears to exist because it is abstracted away from the whole in which it is nothing. Now this invites the following critical question: where do we as finite observers come from? Doesn't dialectical nihilism presuppose our existence as finite observers to explain the illusion of existence? If so, then existence is not really (or not totally) an illusion, since we obviously still exist! This objection, however, is answered very easily, namely, as follows: the existence of the observer is not presupposed; rather, that (apparent) existence is explained as following from the antithetical nature of the nothing. The crucial point is that the nothing, as containing in sublated form all possible beings and antibeings, contains us as observers as well. We, too, inexist in the nothing, because we too are ultimately cancelled by antibeings in the nothing. And as a distinct possibility within the nothing, we have a certain determinacy, a certain possible essence, which includes consciousness and observation. And that is precisely what our phenomenal world amounts to: a possible structure of possible observations made by possible observers who inexist in the nothing – which is simply another way of saying that our observations are not real but illusory. As merely possible, our observations have no actual existence, just like we ourselves have no actual existence. And since we as possible beings within the nothing constitute only an infinitesimally small part of the nothing, our possible experiences and thoughts can never grasp the nothing as a whole, i.e. the totality of all possible beings and antibeings. We observe only fragments of the nothing, fragments which appear to exist because they are abstracted away from the totality in which they are nothing. So given the antithetical structure of the nothing, i.e. its consisting of all possible beings and antibeings, the nothing necessarily contains possible beings with awareness, who appear to be aware of something. In that sense, our (illusory) awareness is just an internal, unactualized, inexistent possibility within the nothing – one possibility among infinitely many other unactualized possibilities.

Russell Standish

Russell Standish's Theory of Nothing: A critique
In recent philosophy a similar thesis has been advanced by the Australian computational scientist Russell K. Standish. His 2006 book Theory of Nothing develops a theory similar to dialectical nihilism in that it describes the ultimate reality, the totality of beings, as a nothing – a nothing in which there nevertheless appear to be 'somethings' due to the limited perspectives of observers who are part of that nothing. Standish's basic argument is that a state where everything possible exists ("the Plenitude" as he calls it) is so mind-bogglingly huge that it is simply inaccessible to the human mind. The scientific background to Standish's idea that everything possible exists is the well-known hypothesis of the infinite multiverse, which has gained considerable currency in present-day physics for various reasons, ranging from cosmology (the hypothesis of eternal inflation) to the many worlds interpretation of quantum mechanics up to more speculative arguments based on mathematical Platonism, i.e. the claim that all mathematically possible objects exist. Standish uses mathematical information theory to show that this infinite multiverse or Plenitude contains zero information and is thus equivalent to nothing. To illustrate his point, he refers to a famous story by Borges, The Library of Babel. The story describes a library containing infinitely many books composed of all possible combinations of letters. Within this fantastic library are the works of all known authors as well as all the possible masterpieces by unknown authors, but also infinitely many books that are complete gibberish. Potentially, the library contains all relevant information, all the answers to our questions. In practice, however, all this information is inaccessible. If you pick out a book, the chance that the book will mean something to you will be infinitesimally small. Thus the library contains virtually no information whatsoever. According to Standish, the Plenitude is like the library of Babel in that its informational content is zero:

"In the [...] theory I present, all possible descriptions of things exist, of infinite length, composed of symbols from an alphabet of your choice... As with Borges's library, the complete ensemble has precisely zero information. The Everything is in fact a Nothing." (Standish 2006: 15) "[We] note that the collection of all possible descriptions has zero complexity, or information content. This is a consequence of algorithmic information theory, the fundamental theory of computer science. There is a mathematical equivalence between the Everything, as represented by this collection of all possible descriptions and Nothing, a state of no information." (Idem: 5)

According to Standish, this informational equivalence of everything and nothing then allows us to answer Leibniz's question and to explain how something emerged from nothing: "In the beginning, there was Nothing, not even a beginning! From out of this Nothing emerged everything we see around us today." (Idem: 21) How does he pull off this magic trick? By placing the observer within the Plenitude. Since the Plenitude contains everything possible, it also contains us, the observers, for whom the Plenitude as a whole is informationally void. Yet as observers we necessarily observe something, and this means we must have a partial view of the Plenitude from the inside. It is because we, as limited observers, observe only part of the Plenitude that the zero information of the whole gives way to non-zero information. According to Standish, that is why there appears to be something rather than nothing. As he puts it: "That some of the descriptions must describe conscious observers who obviously observe something, gives us a mechanism for getting Something from Nothing: Something is the "inside view" of Nothing." (Idem: 5)

I like this idea that "Something is the "inside view" of Nothing" very much. It is basically the same idea that I argued above, namely, that for us – as possible finite observers within the nothing – things appear to exist because we cannot observe the whole in which everything is nothing. But this similarity hides a crucial difference. The trouble comes from Standish's information-theoretic approach. The problem is that the informational nothing is not a real nothing, i.e. not a complete absence of existence, but rather a superabundant existence in disguise. Indeed, as Standish himself stresses, the nothing is really everything, the Plenitude of the infinite multiverse, which to us appears as nothing because we have virtually no cognitive access to it. So when Standish claims he can show how something emerged from nothing through the act of observation, he is clearly cheating, since he is already presupposing the existence of the Plenitude to which the observer belongs. And it is only by thus presupposing the existence of the observer that Standish can claim that the Plenitude is informationally void. The crucial point is, as Standish admits, that information always presupposes an observer: it is only for a receiver that a source contains more or less information. As Standish says: "Information is an observer dependent thing. Shakespeare's "Romeo and Juliet" is nothing more than random gibberish to someone who doesn't know English." (Idem: 12) Thus it is only for an observer that the Plenitude is nothing; the Plenitude is not nothing in itself. So if Standish really wanted to answer Leibniz's question, he should instead have tried to explain why the Plenitude exists. And that's a pretty tall order, because – as we have seen – for Standish the Plenitude contains nothing less than the infinite multiverse from contemporary physics. To explain that, therefore, he would have to fall back on physical explanations. He would have to answer questions like: what caused the Big Bang, what caused the inflation of space, why is the universal wave function the way it is? Thus he would have to fall back on the principle of sufficient reason (PSR). But as we have seen, the idea that the totality of beings falls under the PSR is simply incoherent, which in turn undermines the very assumption that there is a totality of beings. Thus the only consistent answer to Leibniz's question – "Why is there something rather than nothing?" – is to bite the bullet and admit that in truth there is nothing at all, and that existence is just an illusion following from the antithetical structure of the nothing.

Dialectical nihilism vs. negative theology
Standish's information-theoretic approach to the everything-is-nothing idea bears a close (and probably intentional) resemblance to a well-known strategy in classical metaphysics known as negative or apophatic theology. Thus our critique of Standish's approach applies equally well to this tradition of negative theology. In the following I shall say a few words about this, in order to clearly distinguish dialectical nihilism from negative theology, before moving on to my concluding remarks. The basic idea behind negative theology is that God – as the ultimate source of reality – transcends all our cognitive powers: God is so infinitely perfect that we as finite and imperfect creatures simply cannot conceptualize Him. Since all our concepts derive from our finite, imperfect existence, we cannot say what God is: we can only say what He is not. This is the via negativa (negative way) of negative theology: we must progress towards the true vision of God by negating our concepts as inappropriate to God's transcendent nature. Thus we say: God is not good (in our human sense), He is beyond good; God is not infinite (as opposed to and thus limited by the finite), He is beyond infinite; God is not eternal (in time), God is beyond time, etc. Finally we end up with a most perfect being that appears to be completely empty, devoid of any property, an absolute perfection with no determinacy.

Now it is admittedly very tempting to see in this 'empty God' the absolute nothing of dialectical nihilism. This is especially so since negative theology sometimes proceeds to such extremes that even our concept of existence (or being) is said not to apply to God: thus even the proposition that God exists is to be denied! In this way negative theology comes awfully close to 'heretical' nihilism. Take, for example, the following extreme sounding remark by the 9th century theologian Eriugena: "We do not know what God is. God Himself does not know what He is because He is not anything. Literally God is not, because He transcends being." Is Eriugena here denying that God exists? If so, then negative theology would truly be nihilistic. But the final phrase of Eriugena's remark – "because He transcends being" – should make us wary. Eriugena is not saying that God does not exist, he is saying that God transcends our limited conception of existence: God's being is so superlative that it can't be captured by what we mean by "being". Thus in negative theology the via negativa is invariably complemented by a via eminentiae (way of eminence) in which our finite concepts – which are denied of God – undergo a process of absolute maximization or suprematization so as to describe God correctly. In that way we can say: God is not existent, He is supra-existent; God is not wise, He is supra-wise; God is not good, He is supra-good, etc. Granted, for negative theology, these suprematized perfections remain outside the grasp of finite human cognition, but they nevertheless become accessible to us in a mystical vision of God after our minds have been cleansed from all finite concepts. Thus it is clear that, even if negative theology appears to approach nihilism in its negative characterization of God as a 'no-thing', it in fact intends to say the complete opposite of nihilism. Far from being absolutely nothing, the God of negative theology is rather the most perfect supra-being, the creative ground of everything. This dialectical relation to nihilism – where the abyss of nihilism is first approached but then overcome in mystical intuition – is clearly visible in the neo-Platonism of the 3rd century philosopher Plotinus (arguably the arch-father of negative theology). In describing the soul's ascend to God (Plotinus speaks of "the One"), Plotinus clearly recognizes the danger that at first the via negativa results only in a negative conception of the One, an utter emptiness from which the soul shirks away in horror, fearing a fall into atheism:

Plotinus

"The soul or mind reaching towards the formless finds itself incompetent to grasp where nothing bounds it [...]; in sheer dread of holding to nothingness, it slips away. The state is painful; often it seeks relief by retreating from all this vagueness to the region of sense, there to rest on solid ground [...]." (Enneads VI.9.3, 1-6)

The scholar John Peter Kenney, in his book Mystical Monotheism, explains this passage as follows:

"From our position below, the One appears to be empty because we cannot grasp it within our normal conceptual limits. For this reason the soul fears that the One is really nothing at all. It is clear from the subsequent discussion that the soul is mistaken in this, that the One is not lacking; and Plotinus employs the theme of the One as the archē of all reality to enforce the point [...]. A true philosophical study of the One would reveal this to the soul [...], and for this reason the soul should not withdraw from this first principle, the Good." (Kenney 1991: 145)

Thus for Plotinus, nihilism is a mere passageway to the mystical vision of God: although at first appearing to be nothing, God is in fact the opposite, He is the most perfect ground of reality. For dialectical nihilism, in contrast, God is really nothing – or rather: there really is nothing at all, no God, no reality, nothing. Nothingness is the true nature of (illusory) existence. This difference between negative theology and dialectical nihilism becomes crucial in the light of Leibniz's question: "Why is there something rather than nothing?" Here negative theology cannot escape the aporiae of ultimate explanation under the PSR. Although in negative theology the ultimate ground of reality appears to be nothing, it most certainly is not nothing. The One is something, indeed it is the most perfect being. As such its existence needs to be explained, since all beings fall under the PSR. Here negative theology can only appeal to a traditional conception of God as causa sui, whose existence is implied in His essence. But from a rational standpoint, such an explanation cannot hold up, since no being can explain itself. Again, then, dialectical nihilism comes out as the only consistent answer to Leibniz's question. Since the totality of beings cannot possibly be explained, the only rational conclusion is that in truth there is nothing.

Concluding remarks: The spiritual side of dialectical nihilism
If the theory I have presented in the preceding pages sounds just a bit too grim, I should stress that there is also a positive side to dialectical nihilism, akin to Buddhism and Daoism. In Buddhism too we find the idea that the whole of existence is nothing but illusion ("the veil of Maya") and that ultimately nothing exists but nothingness or emptiness ("sunyata"), the "empty fullness" that contains within itself everything possible as pure potentiality. Although the idea that the ultimate nothingness is composed of polar opposites is lacking in Buddhism, it does of course form an essential part of Daoism with its the yin-yang polarity. Though the ultimate source of reality, the Dao, is in itself empty, it does generate the opposition between yin and yang which through their dynamic interplay generate everything else. However, many of the oppositions countenanced by Daoism as manifestations of yin and yang – e.g. heaven and earth, male and female, light and dark – are not ontologically fundamental because they are not truly self-cancelling: the polar opposites do not add up to nothing. The synthesis of day and night, for example, is not nothing but the grayness of twilight. And what results from the unification of male and female? A hermaphrodite, perhaps, but most likely you will get a lot of children, which is as far from nothing as you can get. These dualities, then, are not ontologically fundamental, i.e. they do not add up to nothing. Rather they are superficial dualities taken from daily life. This testifies to the ancient mythological origin of Daoism, which stretches back to shamanism. In contrast, I like to see dialectical nihilism as a rationalization of Daoism, as the rational core inside its mystical shell – though perhaps the stress on the illusory nature of the empirical world brings dialectical nihilism closer to Buddhism than to Daoism, which seems to have a more optimistic view of life. Not that dialectical nihilism necessarily implies a pessimistic view of life. To be sure, the idea that our existence is in fact nothing more than a fleeting illusion, based – literally – on nothing, may not seem very alluring. It can cause a sense of existential anxiety (Heidegger) or even horror, an existential horror vacui so to speak, perfectly described by Hegel:

"The human being is this night, this empty nothing, that contains everything in its simplicity – an unending wealth of many presentations, images, of which none happens to occur to him – or which are not present. This night, the inner of nature, that exists here – pure self – in phantasmagorical presentations, is night all around it, here shoots a bloody head – there another white shape, suddenly here before it, and just so disappears. One catches sight of this night when one looks human beings in the eye – into a night that becomes awful..." (Realphilosophie manuscript of 1805–06)

But maybe this "night of the world" is like the mystic's "dark night of the soul", a necessary passage through pure negativity in which one has to 'die' in order to be reborn again into the light of day.

References
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Atkins, Peter (2011), On Being. Oxford University Press: Oxford.
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-Hawking, Stephen & Mlodinow, Leonard (2010), The Grand Design. Bantam Books: London.
-Kenney, John Peter (1991), Mystical Monotheism: A Study in Ancient Platonic Theology. Brown University Press: Providence.
-Priest, Graham (2009), "The Structure of Emptiness," in: Philosophy East and West, vol. 59, no. 4, pp. 467-480.
-Schopenhauer, Arthur (1958), The World as Will and Representation, Volume I. The Falcon's Wing Press: Colorado.
Standish, Russell (2006), Theory of Nothing. BookSurge Australia.
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