The Routledge Handbook of Panpsychism

William Seager, William E Seager

• Publisher: Routledge
• Year: 2019
• Print ISBN:
  9781138817135
• eBook ISBN:
  9781317510789
• Topic: Philosophy
• Subtopic: Philosophical Metaphysics

Panpsychism is the view that consciousness – the most puzzling and strangest phenomenon in the entire universe – is a fundamental and ubiquitous feature of the world, though in a form very remote from human consciousness. At a very basic level, the world is awake. Panpsychism seems implausible to most, and yet it has experienced a remarkable renaissance of interest over the last quarter century. The reason is the stubbornly intractable problem of consciousness. Despite immense progress in understanding the brain and its relation to states of consciousness, we still really have no idea how consciousness emerges from physical processes which are presumed to be entirely non-conscious.

The Routledge Handbook of Panpsychism provides a high-level comprehensive examination and assessment of the subject – its history and contemporary development. It offers 28 chapters, appearing in print here for the first time, from the world's leading researchers on panpsychism. The chapters are divided into four sections that integrate panpsychism's relevance with important issues in philosophy of mind, philosophy of science, metaphysics, and even ethics:

1. Historical Reflections
2. Forms of Panpsychism
3. Comparative Alternatives
4. How Does Panpsychism Work?

The volume will be useful to students and scholars as both an introduction and as cutting-edge philosophical engagement with the subject. For anyone interested in a philosophical approach to panpsychism, the Handbook will supply fascinating and enlightening reading. The topics covered are highly diverse, representing a spectrum of views on the nature of mind and world from various standpoints which take panpsychism seriously.

1
Introduction

A Panpsychist Manifesto

William Seager

The world is awake. That can stand as a slogan for panpsychism: the view that I will understand here as holding that consciousness is fundamental and ubiquitous in nature. This does not mean that everything is conscious. Whether a particular non-fundamental entity is conscious will depend upon the arrangement of its fundamental constituents given some presumed laws of ‘mental chemistry’¹ which govern the emergence of complex forms of consciousness. So in bare outline panpsychism presents a familiar picture of fundamental features interacting in ways to generate more complex forms, it’s just that the catalog of the fundamental includes consciousness. Nor does panpsychism entail that sophisticated, high-level, human-like consciousness is ubiquitous. The term ‘consciousness’ is notoriously hard to define and the victim of multitudes of more or less well motivated (re)definitions. I aim for a minimal conception. For contrast, compare this expansive notion of consciousness, plucked merely for illustrative purposes from Aaronson (2016): ‘displaying intelligent behavior (by passing the Turing Test or some other means) might be thought a necessary condition for consciousness’. On the minimal conception, consciousness does not at all require that ability to pass the Turing test. Feeling pain (or any other sensation) alone is sufficient for consciousness; consciousness implies only sentience. It’s worth noting this because there is a somewhat pernicious ambiguity lurking here, that between a property and the evidence we have for ascribing it. Although still inaccurate, Aaronson’s dictum is closer to the truth if we change the final phrase to ‘a necessary condition for the ascription of consciousness’. But note that we can have theoretical reasons for ascribing a property without there being any direct observational evidence for the ascription. So, the kind of minimal consciousness in question is not ‘self-consciousness’ or ‘transcendental subjectivity’, or awareness of the self as a subject, or awareness of one’s own mental states, or the ability to conceptualize one’s own mental states as such. Consciousness is simply sentience, or the way things are present (to the mind).

It is undeniable that panpsychism is intuitively implausible. It is frequently subject to derision by philosophers, being labeled ‘absurd’ (Searle 2013) and ‘ludicrous’ (McGinn 1999: 97). Even sympathizers have qualms. Thomas Nagel worries that panpsychism carries the taint of ‘the faintly sickening odor of something put together in the metaphysical laboratory’ (1986: 49). Such denigrations stem from a certain confidence – misplaced I think – in our pre-existing conception of the nature of the physical world and a rather strange lack of confidence in our conception of subjective consciousness. We think we know what matter is, and we think we thereby know that it just is not the kind of thing which is or could be intrinsically conscious. In fact, though commonplace the former belief is demonstratively mistaken, which leaves open the status of the latter claim.

This is not a new thought. In one form or another it dates back at least to 19th-century writers such as Ernst Mach and William James, and in the early 20th century to Bertrand Russell and Arthur Eddington. The basic idea that the nature of matter is not obvious just from our daily interactions with material objects forms the core of Noam Chomsky’s intriguing but somewhat obscure views on the mind-body problem, seemingly leading to Chomsky requiring/expecting a physical-science revolution before consciousness can be understood as a natural phenomenon (see 2000: ch. 4). The staunch anti-panpsychist John Searle sometimes also suggests the need for a revolution in science in order to understand how consciousness is a ‘biological phenomenon’, likening the situation to that of physics prior to the introduction of the electromagnetic field (1992: 101 ff.). Searle’s claim that there is no special problem of consciousness because of the ‘biological powers’ of the brain has always struck me as, therefore, rather strange and one wishes he would explain, not in the details that can be left to science, but just the general mechanism of emergence by which the biological generates consciousness which would then reveal to us where to look for the neurological details. There is considerable recent work devoted to understanding the nature of the physical (see e.g. Montero 2009; Wilson 2006) and much current interest in the associated doctrine of Russellian Monism (see e.g. Alter and Nagasawa 2015). This idea is forcefully expressed in defense of panpsychism in the work of Galen Strawson (see e.g. 2006, 2003 and Strawon’s chapter in this volume).

In the face of this natural antipathy, consideration of the philosophical advantages of panpsychism is the best way for it to gain sympathy. The primary motivator for panpsychism is the problem of consciousness. Over the last fifty years we have witnessed staggering advances in our knowledge of the brain and our ability to observe it in action. As we enter into the search for the elusive neural correlates of consciousness there are truly remarkable developments in mapping the relations between states of consciousness and neural activity.

Perhaps the most astonishing example of our growing knowledge, which is now underpinning practical clinical interventions, is the work of Adrian Owen, who investigates people diagnosed as being in a profound vegetative state. Such patients are incapable of making any overt behavioral response which could signal residual consciousness and have been regarded as completely unconscious. Owen has found that a disturbing number of such patients are in fact ‘locked in’ – fully conscious but cut off completely from their bodies. Using real-time functional MRI, Owen is able to interact with supposedly vegetative subjects by asking them to imagine various activities, such as playing tennis, or walking around their home. It is possible to identify the (no doubt partial) neural correlates of what the subject is imagining and thus open up a channel of communication. Owen is currently working on non-MRI solutions which patients will be able to use outside his laboratory, perhaps even at home.² This is what we can do now. There is little doubt that our ability to discover and track neural correlates of conscious states will expand enormously over the next decades.

Nonetheless, the infamous ‘explanatory gap’ (see Levine 1983) between the physical states of the brain and consciousness remains. Finding neural correlates does not show us how the brain manages to generate or realize consciousness and thereby solve David Chalmers’s ‘hard problem’ (see his 1995, 1996). It seems likely that we will in the near future discover deeper and much more specific neural signatures of conscious states, perhaps involving neural synchronization or distinctive neural or subneuron dynamical activity associated with consciousness. That too won’t reveal how consciousness is produced by the brain: these mechanisms are only more fine-grained correlations. There is a problem of principle here.

Why is that? As hinted previously, the core of the problem is the apparent mismatch between the nature of the physical world as we understand our fundamental theories to have revealed and the subjective, ‘what it is like’ aspect of minimal conscious experience. It feels like something to be awake and this just seems utterly foreign to how we regard and, for many, how we ought to regard the material world.

I take it that physics provides our scientific understanding of that world at the most fundamental level. However, its theories are perpetually provisional and the more or less background metaphysical pictures which they both suggest and spring from have a distressing history of being radically overturned by those of newer theories. And yet it is undeniable that we have accumulated knowledge. This is possible because the metaphysical picture which lurks within or behind our physical theories is not essential to their use and need not be preserved across scientific revolutions, even as explanatory and predictive power is retained and expanded. What is preserved is the relational or structural systems which physical theory maps out and by which it is confirmed and becomes predictively successful.³ These structures are all, ultimately, relations between observable quantities for which we have labels such as ‘mass’, ‘electric charge’, ‘momentum’, etc., all definable in terms of observable motion. Over centuries of development, physical theory has become successively more complex (for example, many kinds of charge beyond that of electric are now recognized) but all new hypotheses link to the relations between observable quantities, albeit sometimes indirectly.

It is unsurprising that nowhere in this system do we find subjectivity, nor in the development of physics is there any need to posit a subjective aspect to nature. The explanatory gap is exactly the problem of how a world which is supposed to be completely described at the fundamental level by a science which has no place or need for subjectivity nonetheless somehow includes the subjective aspect of the world we call ‘consciousness’.

The problem has been recognized for a very long time. In 1714 Leibniz expressed it with his ‘mill argument’ in the Monadology:

Imagine there were a machine which by its structure produced thought, feeling, and perception. We can imagine it as being enlarged while maintaining the same relative proportions, to the point where we could go inside it, as we would go into a mill. But if that were so, when we went in we would find nothing but pieces which push one against another, and never anything to account for a perception … perception, and everything that depends on it, is inexplicable by mechanical principles.

(1714/1989: 215, my emphasis)

Note that Leibniz makes the anti-structuralist point that the causal organization of the mill, or the brain, cannot provide an explanation of the appearance of consciousness even if it is correlated with it.⁴

Leibniz was targeting the so-called ‘mechanical philosophy’ which, roughly speaking, asserted that the material world was, as Newton put it, such that ‘God in the Beginning form’d Matter in solid, massy, hard, impenetrable Particles, of such Sizes and Figures, and with such other Properties, and in such Proportion to Space, as most conduced to the End for which he form’d them’ (1730/1979, Query 31). Of course, Newton did not stop with this characterization but left the strict mechanical view behind by adding that ‘these Particles have not only a Vis inertiæ, accompanied with such passive Laws of Motion as naturally result from that Force, but also that they are moved by certain active Principles’. Gravity is but one example of such ‘principles’, which he also called ‘Powers, Virtues, or Forces’.⁵ Newton expected a scientific chemistry to emerge in time based upon them.

A philosophically purified version of mechanism was much later articulated by C. D. Broad which can stand as the mechanistic ideal, whose essence is:

1. (a) a single kind of stuff, all of whose parts are exactly alike except for differences of position and motion;
2. (b) a single fundamental kind of change, viz, change of position …
3. (c) a single elementary causal law, according to which particles influence each other by pairs …
4. (d) a single and simple principle of composition, according to which the behavior of any aggregate of particles, or the influence of any one aggregate on any other, follows in a uniform way from the mutual influences of the constituent particles taken by pairs.

(1925: 44–5)

This vision is so ethereal that nothing like it has ever been seriously entertained. But the actual mechanical worldview and its successors for a couple of centuries of furious and spectacularly successful development can be seen as implicitly inspired by this pure vision. It expresses well a picture of the world – let’s call it ‘LEGO^® world’ – formed of a very large number of very small parts which are metaphysically independent of each other, have individual identities (albeit ones of very little interest) but which can interact by local causation. The familiarity we have with things like this, think marbles or, indeed, LEGO bricks, is what funds confidence in our conception of matter or the physical and makes it seem intuitive and almost obvious … and very distant from subjectivity.

The mechanical world view leveraged this picture into an intuitive positive conception of the nature of matter: it came in chunks akin to the small particles we are familiar with in ordinary experience: impenetrable, capable of motion and – thanks ultimately to God’s decree – observant of the fundamental rules or laws of nature which governed how these pieces interacted (e.g. conservation of energy). Exactly how and why these material units are ‘forced’ to obey the laws of nature remained (and remains) somewhat obscure. Perhaps the laws’ power is just a primitive metaphysical fact which links properties with the appropriate level of modal force. Perhaps the laws somehow follow from the causal powers of the fundamental entities of the world. Maybe the laws are a mere catalog of universal regularities, or meta-regularities across a set of possible worlds (the ‘nomologically possible worlds’). Perhaps the laws are an imposition of the conscious mind which ‘imposes’ them upon an intrinsically chaotic universe (we find laws of nature because we could not exist in those regions of possibility that were ‘too’ chaotic; a kind of anthropic Kantianism).

In any case, this conception of matter excluded consciousness as one of its properties (except perhaps if God directly and miraculously ‘superadded’ it to a material system⁶) and, in any case, there was no need to posit consciousness to generate all the forms and activities in which matter could participate. As to these forms, we now know that LEGO world is capable of implementing a Turing machine so such a world could at least simulate anything which can be computed (ignoring speculative hyper-computational devices), including quantum mechanics. Such a simulation might be very slow but one should not confuse the simulation runtime with the time internal to the simulation. Perhaps, so to speak, it might take seconds of simulation time to compute one yoctosecond of internal simulation time, but we can suppose that the simulation lives in an eternal and spatially infinite world so there is no principled limitation here (we can suppose the physics of the simulation world is unconstrained by anything except its being a LEGO world). Presumably, our entire universe, or at least the observable universe, can thus be simulated given that the number of possible initial conditions (the degrees of freedom of the big bang) is finite (which seems to be implied by current theory, e.g. the holographic principle and possible theories of quantum gravity).

So the LEGO world conception is in fact...

Table of contents

• Cover
• Half Title
• Series
• Title
• Copyright
• Contents
• Notes on Contributors
• Preface to the Handbook
• 1 Introduction: A Panpsychist Manifesto
• Part I Historical Reflections
• Part II Forms of Panpsychism
• Part III Comparative Alternatives
• Part IV How Does Panpsychism Work?