Wednesday, March 29, 2017

Leibniz's Question, the Crisis of Physicalism, and the Return of Absolute Idealism


Introduction
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 ‘the 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 of 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.

G.W. Leibniz (1646-1716)
In this post I will investigate this mysterious notion – the self-causation of reality – in light of the current crisis of materialism or what is nowadays rather known as physicalism, i.e. the ontology that takes (completed) physics as the final description of reality. It is a well-known fact that physicalism is presently under increasing attack, mainly by philosophers who point out the irreducibility of consciousness to a physicalist framework. Since self-causation is generally deemed impossible on a physicalist framework, the present crisis of physicalism means that the notion of self-causation gets a second chance.

Moreover, since it is
consciousness which is largely responsible for bringing on this crisis of physicalism, the question arises whether consciousness is perhaps the key to understanding the self-causation of reality. This takes us in the direction of Absolute Idealism, where the self-causing essence of reality is generally conceived of in terms of self-consciousness. Thus Absolute Idealism can be broadly summarized as the claim that reality exists because it is thought and/or experienced by an Absolute Mind, which in turn exists because It thinks/experiences itself. It is through its self-consciousness, therefore, that the Absolute Mind lifts itself into existence – at least according to such Absolute-Idealist thinkers such Plotinus, Shankara, Fichte, Schelling, Hegel and Royce.

In the final sections of this post I will discuss two common mistakes about Absolute Idealism: (1) that Absolute Idealism was first and foremost a creature of the 19th century, invented by post-Kantian German Idealists (Fichte, Schelling and above all Hegel) and then passed on to Anglo-American Idealists (Green, Bradley, McTaggart, Royce); and (2) that Absolute Idealism was refuted at the beginning of the 20th century by the founding fathers of Analytic Philosophy, Russell and Moore, as well as by empirical science, and that Absolute Idealism has henceforth become obsolete. Both mistakes will be corrected by taking a closer look, firstly, at the millennia-old history of Absolute Idealism in both Eastern and Western philosophy and, secondly, at the remarkable return of Absolute-Idealist themes in contemporary Analytic Philosophy and physics.

Plotinus: The originator of self-causation in Western philosophy
As noted in the Introduction, we need the notion of self-causation in order to answer Leibniz’s famous question: “Why is there something rather than nothing?” Since there is nothing outside of reality as a whole, the reason for its existence can only lie within reality itself. In that sense, then, reality must be self-causing. This argument is nothing new and I certainly claim no originality for it. It has ancient roots in Western philosophy, going back as far as Plotinus, who appears to have been the very first Western philosopher to speak of God (or rather
the One in Plotinian terminology) as self-caused (cf. Gerson 2011: 34). Thus, to underscore the self-causing nature of the One, Plotinus says that “it itself makes itself [...] from nothing” (Ennead VI, 8, 7).

Plotinus (ca. 204/5-270)
introduced the notion of
self-causation in Western
philosophy
Clearly, Plotinus does not mean here that the One has literally emerged out of nothing, as if at first there was nothing and then suddenly the One sprang into existence, like a ‘hiccup from the void’. Plotinus surely agreed with the supremely Greek principle that from nothing only nothing can come (ex nihilo nihil fit), which is precisely the reason why reality can ultimately come only from itself, such that we must postulate self-causation at the origin of reality. So when Plotinus says that the One makes itself “from nothing”, what he means is that nothing preceded the One (not even ‘nothing’), because the One is the all-inclusive reality. “The One is all things,” Plotinus writes, which is precisely the reason why the One qua “really existent All is in nothing; for there is nothing before it” (Enneads V, 2, 1 & VI, 4, 2). The One, then, is for Plotinus the self-causing core of all-inclusive reality, which must be self-causing precisely because there is nothing outside of it.

Physicalism and the fig-leaf conception of self-causation
From Plotinus this argument for a self-causing core to reality – what Pascal called “the God of the philosophers” – found its way to later philosophers, notably premodern and early modern philosophers such as Augustine, Descartes and Spinoza. In still later philosophers, however, we see this notion of self-causation gradually disappearing from view –
even in philosophers who agree with the argument motivating this notion, namely, the argument that reality must contain the reason for its own existence, since there is nothing outside of it.

John Leslie (1940-), one of the few
contemporary philosophers who
still use the notion of self-causation
Thus we see modern philosophers who agree with this argument use all kinds of fig-leaf conceptions of self-causation, i.e. euphemistic concepts that basically mean the same thing but sound ‘less offensive’ – concepts such as “explanatory self-subsumption” (Nozick), “self-explanation” (Rescher), “cosmic bootstrapping” (Atkins), and “self-excitation / self-synthesis” (Wheeler). (A notable exception, however, is John Leslie who, as a Neoplatonizing Spinozist, is quite happy to invoke self-causation.)

Why this dread of self-causation, when the point these thinkers wish to make – that the reason for reality's existence can only lie within it – clearly invites that notion? The reason behind this dread, I venture, lies in the rise of
physicalism as the dominant ontology of the modern age. I define “physicalism” as the ontology that takes reality to be primarily physical reality as described by mathematical-experimental physics. The truth of physicalist ontology has seemed – please note the past tense! – almost self-evident in light of the stunning experimental successes of modern physics (from classical mechanics to relativity and quantum theory). Physicalism was further reinforced by the victory of Neo-Darwinism, which seems to show that our consciousness is ‘just’ an evolutionary product of mechanical processes of molecular reproduction and natural selection.

Due to the resulting dominance of physicalism, the concept of causation
became virtually synonymous with “physical causation”. One could say that of the rich Aristotelian array of four types of causality – formal, material, final and efficient – only one survived: a denuded notion of efficient causality, limited to the physical realm and restricted by the mathematical laws uncovered by physics. But if physical causation is the only form of causation around, then obviously self-causation doesn't make much sense. Physical reality is essentially spatiotemporal, and – as I have argued extensively in my previous post – self-causation is impossible in time (so if reality has a self-causing cause, the latter must be atemporal).

This
is the main reason why modern thinkers avoid the notion of self-causation (even when agreeing with the general idea behind it), the reason being their – conscious or unconscious – acceptance of physicalism as the dominant ontology of our age. Modern science and philosophy have become so saturated with physicalism that self-causation has literally become unthinkable in current modes of thinking.

The crisis of physicalism
As noted, however, the truth of physicalism
has seemed almost self-evident – meaning that this is now no longer the case. The truth of physicalism as a general ontology is increasingly put into doubt by both philosophers and scientists. It seems fair to speak of a growing crisis of physicalism, mainly brought on by the troublesome phenomenon of consciousness.

The crisis stems partly from developments internal to physics, notably the notorious measurement problem in quantum mechanics and the curious role the latter accords to the conscious choices made by observer (cf. Rosenblum & Kuttner 2011). This does not mean, of course, that the truth value of physics is being questioned, which would be absurd in light of the tremendous experimental success of modern physics (
especially quantum mechanics). But the assumption, which once seemed self-evident to an earlier generation, that physics is the natural ally of physicalism, is increasingly put into question.

David Chalmers (1966-) pioneered
the Hard Problem of Consciousness
But the ontological meaning of quantum mechanics is notoriously hard to interpret (let alone its relation to consciousness), so the case of quantum mechanics has certainly not been decisive in bringing on the crisis of physicalism. Mostly, therefore, this crisis stems from purely philosophical work done on the so-termed “Hard Problem of Consciousness”, i.e. the conceptual impossibility to explain consciousness fully in physical terms. Over the past few decades various strong conceptual arguments for this explanatory irreducibility of consciousness have been developed, notably the “knowledge argument” and the “conceivability argument” (cf. Chalmers 1996).

As a result, the philosophical landscape has changed dramatically, from a thoroughly physicalist one, where consciousness was accorded no independent status apart from the physical, to a much more ambiguous landscape with different philosophical positions stressing the ontological independence of consciousness – positions such as (Substance and Property) Dualism, Russellian Monism, Panpsychism, Panprotopsychism, Idealist Monism, etc.

The renewed relevance of Absolute Idealism
But if this is so, if the ruling days of physicalism are over, then perhaps the notion of self-causation can get a second chance? If consciousness is not reducible to the physical, then obviously there must be a strictly mental form of causation, i.e. a type of causality that is intrinsic to consciousness alone. After all, even if irreducible to the physical, consciousness remains ruled by causality: stimulation of the senses generally causes sensory perceptions, perceptions cause emotional and cognitive reactions, one thought leads to another, bodily movements follow upon exertions of the will, etc. Thus, given the irreducibility of consciousness, we must admit the existence of mental causation as irreducible to physical causation. But then the question arises: does mental causation allow us to make sense of the self-causation needed to explain reality as a whole?

To this question the philosophical tradition of
Absolute Idealism answers with a resounding “Yes”. To see why, let us note its central claim, which – although worked out differently by different thinkers – can be summarized as follows: everything exists because it is thought and/or experienced by an Absolute Mind, which in turn exists because It thinks/experiences Itself. Thus the Absolute Mind lifts itself into existence (is causa sui, as philosophers up to Spinoza would say) by being aware of itself. This notion of an Absolute Self-Awareness as the self-causing cause of all reality is the central thread running through the millennia-old tradition of Absolute Idealism, the thread that ties together various philosophers who are sometimes separated by continents and millennia.

Josiah Royce (1855-1916)
carried the tradition of
Absolute Idealism into
the 20th century
Thus e.g. the Vedantic sages of the Upanishads: “Brahman, indeed, was this in the beginning. It knew itself only as ‘I am Brahman’. Therefore it became all.” (Radhakrishnan 1953: 168) Thus Plotinus: “The One [...] made itself by an act of looking at itself. This act of looking at itself is [...] its being.” (Ennead VI, 8, 16, 19-21) Thus Schelling: “[I]t is through the self's own knowledge of itself that that very self first comes into being.” (Schelling 1800 [2001]: 27) Thus Royce: “[I]f whatever exists, exists only as known, then the existence of knowledge itself must be a known existence, and can finally be known only to the final knower himself, who, like Aristotle's God, is so far defined in terms of absolute self-knowledge.” (Royce 1899 [1959]: 400) Prompted by the tradition of Absolute Idealism, therefore, our question becomes: does self-awareness furnish us with a form of mental causation that amounts to self-causation?

The self-causing capacity of self-awareness
Why should self-awareness be seen as self-causing? The answer given by the various Absolute Idealists, even if it often remains largely implicit, is nevertheless clear: the self-aware subject essentially
is its own object of awareness, and therefore it only exists insofar as it is aware of itself. In other words: its existence is its awareness of itself. So, by being aware of itself, it bootstraps itself into existence. Adapting Berkeley’s famous formula “esse est percipi”, we can say that the esse of self-awareness is its percipi per se – that is: its being is its being perceived by itself. This does not mean, of course, we should accept Berkeleyan idealism tout court, only that Berkeley’s formula is especially well-suited to clarify the nature of self-awareness: its existence through self-perception (here, obviously, I presuppose that awareness of something is a kind of perception – but this is largely a verbal issue).

We should, however, beware not to extend this self-producing capacity of self-awareness to its empirical properties. As an empirical individual, I am aware of myself as a physical organism, with a particular name, a social identity, having all kinds of thoughts and feelings, etc. But surely my awareness of myself as having those properties does not imply my having created them. My self-awareness does not imply my being self-caused
as an empirical individual. Empirically, I exist to a large extent independently from the awareness I have of myself. The self-causing capacity of self-awareness, then, can apply only to the non-empirical aspect of self-awareness, or what I call pure self-awareness.

In order to uncover this pure self-awareness, consider the fact that to be truly self-aware it is not enough that you are aware of your empirical properties, what your body looks like, what you are doing right now, etc. To be truly self-aware, you must also be aware of the fact
that you are self-aware. That is: self-awareness must itself be one of the objects of which it is aware. This follows from the essence of self-awareness, since “a self-awareness unaware of itself” is clearly a contradiction in terms. Self-awareness, then, must have a circular structure: it must include self-awareness of self-awareness. This is what I mean by “pure self-awareness”. Note that the essential circularity of pure self-awareness fits the circularity required for self-causation hand in glove: just as the self-causing cause must be its own effect, so pure self-awareness must be its own object of awareness.

Is pure self-awareness
self-producing?
The wager of Absolute Idealism is that this is much more than just a vague analogy between two circularizes: it is an intrinsic connection, an essential identity. After all: pure self-awareness cannot exist without being aware of itself. This circularity, therefore, constitutes a necessary condition for the existence of pure self-awareness. And, clearly, it is also a sufficient condition for that existence, since if there is an awareness that is its own object of awareness, then that awareness ipso facto amounts to self-awareness (however empty and lacking in empirical properties it may otherwise be). Thus the essential circularity of pure self-awareness implies its self-causing nature, since that circularity is both a necessary and sufficient condition for its existence. By being aware of itself, pure self-awareness bootstraps itself into existence.

Hofstadter on the “strange loop” of self-awareness
The self-causing capacity of self-awareness has not just been noticed by philosophers with a metaphysical axe to grind. This capacity for self-causation, or at least the semblance thereof, has also been noted by the cognitive scientist Douglass Hofstadter, who focuses on self-referential structures (“strange loops”) as offering the key to the mystery of consciousness: “In the end, we are self-perceiving, self-inventing,
[...] little miracles of self-reference.” (Hofstadter 2007: 363) Commenting on the “strange loop” of self-awareness, Hofstadter notes how this seemingly implies its self-causation: “It is almost as if this slippery phenomenon called “self-consciousness” lifted itself up by its own bootstraps, almost as if it made itself out of nothing.” (Idem: xii)

But note Hofstadter's reservation: “almost as if”. What gets in the way of Hofstadter’s full endorsement of the bootstrapping of self-consciousness is his adherence to physicalism, which forbids self-causation. As a physicalist, Hofstadter takes consciousness to be ultimately reducible to physical processes (the brain interacting with its environment). Hence his conclusion that the self-causing aspect of self-awareness must be an illusion, because physical processes (as they take place in time) cannot be self-causing. Thus he takes the self-causing aspect of self-awareness to be ultimately an illusion, a “mirage” (idem: 363), a surface appearance produced by myriad micro-feedback processes in the brain, processes that obey the standard laws of physics: “The problem is that in a sense, an “I” is something created out of nothing. And since making something out of nothing is never possible, the alleged something turns out to be an illusion, in the end, but a very powerful one.” (Idem: 292)

But here the Hard Problem of Consciousness comes to our rescue. The Hard Problem of Consciousness shows the irreducibility of consciousness to physical and computational structures. This means that the self-producing structure of self-awareness need not be illusory simply because it is ruled out by physics. We see, therefore, that the Hard Problem of Consciousness opens the possibility that the self-causation of self-awareness is genuine.

Two common mistakes about Absolute Idealism
There are, however, two common mistakes about Absolute Idealism which stand in the way of its proper understanding and evaluation – mistakes which we therefore have to correct. These common prejudices are (1) that Absolute Idealism was first and foremost a creature of the 19th century, originating with the post-Kantian German Idealists (Fichte, Schelling and Hegel) and then taken up and developed further by the Anglo-American Idealists (Green, Bradley, McTaggart, Royce); and (2) that Absolute Idealism was subsequently, at the beginning of the 20th century, refuted by the founding fathers of Analytic Philosophy, Moore and Russell in particular, as well as by empirical science, and has since then become obsolete.

The Sanskrit term "Upanishad" means "sitting down near"
and refers to the student sitting down near the teacher
in order to receive esoteric teaching
As regards the first prejudice, it is easily dispelled by even a cursory glance at the millennia-long history of Absolute Idealism in both Western and Eastern philosophy. This history arguably began in ancient India, notably in the Vedantic philosophy of the Upanishads (around the 7th century BCE). From there it migrated to the West, where it reached its first fully mature form in the Neoplatonism of Plotinus (3rd century CE – it is quite possible that Plotinus was influenced by the Vedanta; see Bréhier 1958). To a large extent the post-Kantian German Idealists merely rediscovered / reconstructed this new type of Idealism inaugurated in the West by Plotinus (cf. Beierwaltes 2004). Plotinus, then, was not just the originator of the notion of self-causation in Western philosophy; he was also the first Western philosopher to make the Absolute-Idealist identification of the self-causing cause of reality with self-awareness.

Bertrand Russell (1872-1970):
"It was towards the end of 1898 that
Moore and I rebelled against both
Kant and Hegel. Moore led the way,
but I followed closely in his footsteps."
(Bertrand Russell, My Philosophical
Development
. London: Allen and
Unwin, 1959, p.42.)
Let us now turn to the second prejudice. Hasn’t Absolute Idealism been refuted by the founding fathers of Analytic Philosophy, Moore and Russell? And hasn’t it since then become obsolete? Well, histories of philosophy tend to present each new school of philosophy as arising by refutation of its predecessor, whereas the actual fact of the matter is often a lot more complicated. This holds no less for the “creation myth” of Analytic Philosophy, according to which the latter emerged by overthrowing the Absolute Idealism of the British Hegelians (who were the teachers of Moore and Russell). Recent historical scholarship has done much to discredit this triumphalist history. As Hylton notes in his Russell, Idealism, and the Emergence of Analytic Philosophy: “For every argument that Moore or Russell could mount against Idealism, there is an idealist reply which points out a distinction that is being neglected, or one that is drawn erroneously; an assumption smuggled in, or the sense of a term distorted.” (Hylton 1990: 105) In addition to this comes the fact that Absolute Idealism is currectly making something of triple comeback: two comebacks in Analytic Philosophy itself, and one comeback in contemporary physics. I will discuss these developments below.

The Normative Idealism of the Pittsburgh Hegelians
To begin with Analytic Philosophy, here we see Absolute Idealism return in both epistemology and the philosophy of mind. In epistemology we find the so called “Pittsburgh Hegelians” John McDowell and Robert Brandom, who have made a remarkable return to both Kant and Hegel by pointing out that conceptuality and rationality in general are intrinsically normative, having to do with how people
ought to think rather than with how they factually think. On the basis of this “normativity of the conceptual” they argue for a Hegelian form of conceptual holism, such that – to paraphrase Hegel – the truth lies only in the conceptual whole that includes empirical reality (cf. Redding 2007). For given the conceptually laden impact of empirical experience on thought, the empirical world must have a normative significance that cannot be accounted for in strictly physicalist terms. According to McDowell and Brandom, therefore, the empirical world turns out to have a normative-conceptual structure that is best understood in terms of Hegel’s Absolute Idealism, where there is nothing outside of conceptual whole of “Absolute Knowledge”. I hope to be able to say more about Pittsburgh Hegelianism in later posts on this blog.

From the Hard Problem of Consciousness to Absolute Idealism
In the philosophy of mind, as we have already noted, we see the Hard Problem of Consciousness (HPC) give rise to serious doubts concerning the physicalist ontology adopted by earlier analytic philosophers. As a result, the philosophical landscape has changed dramatically, from a thoroughly physicalist one, where consciousness was accorded no independent status apart from the physical, to a much more ambiguous landscape with different competing philosophical positions stressing the ontological independence of consciousness – positions such as Property Dualism, Russellian Monism, Panpsychism, Micropsychism, and Idealist Monism.

In this context Absolute Idealism, too, is being reconsidered as perhaps the best response to the HPC (cf. Sprigge 1983; Hutto 2000; D'Oro 2005). The simple but crucial point here is that if consciousness is irreducible to physical reality (as the HPC shows), then mind-body interaction is only possible if the converse reduction holds, i.e. if physical reality reduces to consciousness. But this claim, that physical reality reduces to consciousness, amounts to Idealist Monism. Therefore: the HPC + mind-body interaction = Idealist Monism. And Idealist Monism is only a few steps away from Absolute Idealism.

The mystery of mind-
body interaction
Let us consider the above argument in some more detail. On the one hand, the HPC shows that consciousness cannot be explained in exclusively physical terms, such as brain activity. Thus the HPC refutes physicalism. But how, then, do consciousness and physical reality interact? There is no denying that such interaction takes place. Stimulate the brain and as a result consciousness changes. Conversely, a conscious exertion of the will usually results in limbs moving etc. How is this mind-body interaction possible if physicalism is false? The HPC leaves open only two possibilities: either consciousness and physical reality are two mutually independent realms of reality (Dualism) or physical reality is ultimately explainable in terms of (i.e. reduces to) consciousness alone (Idealist Monism). But, clearly, Dualism cannot account for mind-body interaction. For how could two utterly different and mutually independent realities possibly interact? (See e.g. the absurdity of Descartes' pineal gland.) Thus, since the HPC leaves open only these two possibilities, Dualism and Idealist Monism, the latter option must be true – that is: physical reality must ultimately reduce to consciousness, because consciousness can obviously interact with consciousness.

In other words: if we conceive of physical reality as a kind of manifestation of consciousness itself, then mind-body interaction becomes unproblematic. For then this interaction is ‘simply’ a case of consciousness interacting with one of its own manifestations, thus with itself in a sense. Of course, there really is nothing ‘simple’ about such Idealist Monism, since we still need an account of
how consciousness produces the physical.

But Idealist Monism is not necessarily the same as Absolute Idealism. So how do we get from the former to the latter? Here the following consideration seems to be relevant. We already saw that the HPC saves the self-causation of self-awareness from the critique by physicalism. But the relation works the other way as well: the self-causation of self-awareness
explains the HPC, i.e. it explains why consciousness is irreducible to physical reality. From the self-causation of self-awareness, after all, we have to conclude that self-awareness is the self-causing cause of reality as such – in other words: consciousness (in the form of self-awareness) is the basic ‘stuff’ of which reality consists, reality’s most primitive constituent. From this it obviously follows that consciousness is irreducible: it cannot be explained in terms of anything besides itself. Consciousness can only be explained in terms of consciousness, ultimately in terms of self-awareness.

Thus, when Chalmers (1995: 200) writes: “There is nothing that we know more intimately than conscious experience, but there is nothing that is harder to explain”, he
thinks he is stating a paradox (“despite its intimacy, we can't explain consciousness”), whereas in fact he is stating the very explanation of consciousness’ irreducibility. For it is precisely the intimacy with which we know conscious experience (i.e. the self-evident experience of our own self-awareness, with its self-causing capacity) that explains why consciousness is reality’s most basic constituent.

John A. Wheeler (1911-2008)
The Absolute Idealism of Wheeler’s Self-Observing Universe
Beyond philosophy, moreover, we see Absolute Idealism return in contemporary physics (
the paradigm of empirical science, at least for most analytic philosophers), notably in John A. Wheeler's theory of the Self-Observing Universe. Drawing on Idealist tendencies in both quantum mechanics (the observer dependency of wave function collapse) and digital physics (the constitutive importance of information for physical reality), the theoretical physicist Wheeler argued that the totality of physical reality – i.e. the universe – brings itself into existence by evolving those conscious subjects whose scientific observations and binary yes/no questions give “tangible reality” to the mathematical structure which is the universe. As Paul Davies summarizes: “Conventional science assumes a linear logical sequence: cosmos → life → mind. Wheeler suggested closing this chain into a loop: cosmos → life → mind → cosmos.” (Davies 2006: 281)

Wheeler's U diagram of
the Self-Observing Universe
For Wheeler, then, the universe is the self-creating Absolute, the Whole that brings itself into existence through mediated self-observation (mediated, namely, by the observers existing in the universe). In this way Wheeler resurrected the core idea of Absolute Idealism (the self-creation of Absolute Self-Awareness) within the context of contemporary physics. To be sure, Wheeler's theory of the Self-Observing Universe is so far nothing more than a hypothesis, or rather – as Wheeler himself stressed – an “idea for an idea”. It is by no means yet an empirically testable hypothesis, let alone a well-established scientific theory. Nevertheless, the fact that it presents a distinct scientific possibility, worthy of further investigation, is acknowledged by many physicists. (I discuss Wheeler’s hypothesis of the Self-Observing Universe in more detail here and here.) All in all, then, Absolute Idealism is still a live option, both in philosophy and science.

References
-
Beierwaltes, Werner (2004), Platonismus und Idealismus. Frankfurt: Vittorio Klostermann.
-Br
éhier, Émile (1958), The Philosophy of Plotinus. Chicago: The University of Chicago Press.
-Chalmers, David (1995), “Facing Up to the Problem of Consciousness,” in:
Journal of Consciousness Studies 2(3): 200-19.
-(1996),
The Conscious Mind: In Search of a Fundamental Theory. New York and Oxford: Oxford University Press.
-Davies, Paul (2006),
The Goldilocks Enigma: Why is the Universe Just Right for Life? London: Penguin Books.
-D’Oro, Giuseppina (2005), “Idealism and the philosophy of mind,” in:
Inquiry 48 (5): 395-412.
-Gerson, Lloyd (2011), "Goodness, Unity, and Creation in the Platonic Tradition", in: John F. Wippel (ed.),
The Ultimate Why Question: Why Is There Anything at All Rather than Nothing Whatsoever?, pp. 29-42. Washington, D.C.: The Catholic University of America Press.
-Hofstadter,
Douglas (2007), I Am a Strange Loop. New York: Basic Books.
-Hutto, Daniel D. (2000),
Beyond Physicalism. Amsterdam: John Benjamins Publishing Company.
-Hylton,
Peter (1990), Russell, Idealism, and the Emergence of Analytic Philosophy. Oxford: Oxford University Press.
-Plotinus,
Enneads, translation by A.H. Armstrong, Loeb edition.
-Radhakrishnan,
Sarvepalli (1953), The Principal Upanishads. New York: Harper.
-Redding,
Paul (2007), Analytic Philosophy and the Return of Hegelian Thought. Cambridge: Cambridge University Press.
-Rosenblum, Bruce & Kuttner, Fred (2011),
Quantum Enigma: Physics Encounters Consciousness. Oxford: Oxford University Press.
-Royce, Joshiah (1899 [1959]),
The World and The Individual, First Series: The Four Historical Conceptions of Being. New York: Dover Publications.
-Schelling, F.W.J. (1800 [2001]),
System of Transcendental Idealism. Translated by Peter Heath. Charlottesville: University Press of Virginia.
-Sprigge, Timothy L.S. (1983),
The Vindication of Absolute Idealism. Edinburgh: Edinburgh University Press.

Wednesday, February 15, 2017

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, a
lthough 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. Is 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 an additional 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 slight 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.