New Waves in Philosophy of Mind

M. Sprevak, J. Kallestrup, M. Sprevak, J. Kallestrup, M. Sprevak, J. Kallestrup

• Publisher: Palgrave Macmillan
• Year: 2014
• ISBN:
  9781137286734
• Topic: Psicologia
• Subtopic: Psicologia cognitiva e cognizione

Philosophy of mind is one of the core disciplines in philosophy. The questions that it deals with are profound, vexed and intriguing. This volume of 15 new cutting-edge essays gives young researchers a chance to stir up new ideas. The topics covered include the nature of consciousness, cognition, and action.

Part I

Metaphysics of Mind

1

The Cartesian Argument against Physicalism

Philip Goff

I’m an analytic metaphysician who thinks analytic metaphysicians don’t think enough about consciousness. By ‘consciousness’ I mean the property of being a thing such that there’s something that it’s like to be that thing. There’s something that it’s like for a rabbit to be cold or to be kicked or to have a knife stuck in it. There’s nothing that it’s like (or so we ordinarily suppose) for a table to be cold or to be kicked or to have a knife stuck in it. There’s nothing that it’s like from the inside, as it were, to be a table. We mark this difference by saying that the rabbit, not the table, is conscious.

The property of consciousness is special because we know for certain that it is instantiated. Not only that, but we know for certain that consciousness as we ordinarily conceive of it is instantiated. I am not claiming that we know everything there is to know about consciousness or that we never make mistakes about our own conscious experience. My claim is simply that one is justified in being certain – believing with a credence of 1 – that there is something that it’s like to be oneself, according to one’s normal understanding of what it would be for there to be something that it’s like to be oneself.

This makes our relationship with consciousness radically different from our relationship with any other feature of reality. Much metaphysics begins from certain ‘Moorean truths’ – truths of common sense that it would be intolerable to deny. Perhaps it is a Moorean truth that some or all of the following things exist: persons, time, space, freedom, value, solid matter. But it would be difficult to justify starting metaphysical enquiry from the conviction that these things must exist as we ordinarily conceive of them. We must remain open to science and philosophy overturning our folk notions of what it is for someone to be free or for something to be solid or for time to pass.

Matters are different when it comes to consciousness. It is not simply that I can gesture at some property of ‘consciousness’ with folk platitudes and have confidence that something satisfies the bulk of those platitudes. When I entertain the proposition <there is something that it’s like to be me>, I know that that very proposition (not it or some revision of it containing a slightly different concept of ‘being something such that there’s something that it’s like to be it’) is true.

You can’t build a satisfactory metaphysical theory wholly from the datum that there is consciousness; that datum is after all consistent with solipsism. We must continue to rely on Moorean truths, empirical data and the weighing of theoretical virtues in trying to formulate our best guess as to what reality is like. But because the datum that there is consciousness (as we ordinarily conceive it) is unrevisable it ought to occupy a central place in enquiry, a fixed point around which other considerations revolve. I call an approach to analytic metaphysics that grants the reality of consciousness this central place ‘analytic phenomenology’.

The potential of this datum is grossly underexplored; it has arguable implications for the nature of time, persistence, properties, composition, objecthood and personal identity. Time will tell, but it is possible that with an agreed source of unrevisable data, analytic phenomenologists may achieve some degree of consensus on certain key questions – a goal which has so far eluded other schools of metaphysics.

Perhaps the most famous alleged implication of the reality of consciousness is the falsity of physicalism. In this paper I focus on Descartes’s conceivability argument against the historial ancestor of physicalism: materialism. In my undergraduate lectures, these arguments against materialism were presented as objects for target practice rather than serious evaluation. At the time it seemed to me that there was more to the arguments than they were being given credit for. I now think Descartes’s Meditations provides the resources for a sound argument against standard contemporary forms of physicalism. In what follows I present this argument.

In the final section, I highlight a distinctive advantage of this argument: if sound, it demonstrates the non-physicality not only of sensory experience but also of thought.

1 The second meditation and the refutation of analytic functionalism

Physicalism is the metaphysical view that nothing in actual concrete reality is anything over and above the physical. There is a great divide amongst physicalists over the epistemological implications of that metaphysical doctrine. A priori physicalists, whom I consider in this first section, believe that all facts are a priori entailed by the physical facts. If you knew the intrinsic and extrinsic properties of every fundamental particle and field and you were clever enough, you could in principle work out a priori all the other facts: what the chemical composition of water is, who won the Second World War, how many number 1 hits the Beatles had, and so on.¹

Perhaps the trickiest case for the a priori physicalist is mentality. Prima facie it doesn’t seem possible to move a priori from the kind of facts brain science delivers to the facts about consciousness. A colour-blind brain scientist could know all the physical facts about colour experience without knowing what it’s like to see colours. A brain scientist who’s never tasted a lemon could not work out how one tastes from poking around in someone’s brain.² At least that’s how things seem. If she wants to have a plausible, fully worked out view, the a priori physicalist cannot just brutally assert that contrary to appearances, the mental facts do follow a priori from the physical facts but must give some plausible account of mental concepts which has this implication.

The standard way of doing this is to adopt some form of analytic functionalism; that is, to give some kind of causal analysis of mental concepts. The straightforward analytic functionalist says that mental concepts denote higher-order functional states. For example, the concept of pain denotes the state of having some more fundamental state that ‘plays the pain role’ – that is, roughly speaking, that responds to bodily damage by instigating avoidance behaviour. On the more subtle ‘Australian’ form of analytic functionalism defended by David Armstrong and David Lewis, mental concepts are non-rigid designators which pick out certain states in virtue of the higher-level functional states they realize.³ Just as the concept ‘head of state’ picks out in each country the individual that happens to be the head of state in that country, so ‘pain’ picks out in each population the state that happens to play the pain role in that population.

It is clear that both forms of analytic functionalism are forms of a priori physicalism. Suppose Jennifer’s c-fibres are firing, and the firing of c-fibres is the state that plays the pain role both in Jennifer and in the human population in general. For the straightforward analytic functionalist, if I know all the physical facts I will be able to work out that Jennifer is in a state that plays the pain role and can infer from this information that Jennifer is in pain. For the Australian analytic functionalist, if I know all the physical facts I will know that Jennifer instantiates the state that plays the pain role in humans and can infer from this information that Jennifer is in pain. In either case, the mental facts can be deduced from the physical facts.

The second meditation provides the resources for a decisive refutation of both of these forms of analytic functionalism. By the end of the second meditation I have doubted the existence of my body and my brain and of the entire physical world around me. For all I know for certain, my apparent experience of all these things might be an especially vivid hallucination instigated by an omnipotent evil demon. This demon might have brought me into existence just a moment ago – with false memories of a long history and expectations of a similar future – and may destroy me a moment hence. I discover that the only thing the demon cannot be deceiving me about is my own existence as a thinking thing: no matter how much the demon is deceiving me, I must exist as a thinking thing in order to be deceived.

At the end of this guided meditation, when I have doubted the existence of anything physical whilst at the same time enjoying the certain knowledge that I exist as a thinking thing, I find I am conceiving of myself as a pure and lonely thinker: a thing that has existence only in the present moment, and that has no characteristics other than its present mode of thought and experience.⁴ The fact that I can conceive of myself as a pure and lonely thinker is inconsistent with the analytic functionalist analysis of mental concepts. For the straightforward analytic functionalist, it is a priori that something has a given mental state if and only if it has the higher-order state of having some other state that plays the relevant causal role. However, a pure and lonely thinker has no states other than the mental states themselves: its mental states are not realized in anything more fundamental. If straightforward analytic functionalism is true, a pure and lonely thinker is inconceivable. And yet a pure and lonely thinker is not inconceivable; the second meditation guides us to its conception.

For the Australian analytic functionalist, it is a priori that something is in pain if and only if it has the state that plays the pain role in its population. But a pure and lonely thinker does not have a population; it is alone in its world. If Australian analytic functionalism were true, a pure and lonely thinker would be inconceivable. Yet by the end of the second meditation we end up conceiving of one.

Lewis does suggest at one point that the population relevant to determining the application of mental concepts might be the concept user’s population rather than the population of the creature the concept is being applied to.⁵ However, when I reach the end of the second meditation, I am supposing that I am alone in the universe and hence am not a member of any population. If Lewis were right about the reference fixing description of pain, then ‘pain’ would have no application in such a conceivable scenario, just as the concept ‘head of state’ has no application in a scenario where there are no countries. Yet if I read the second meditation when I have a headache, I end up conceiving of a scenario in which the concept ‘pain’ evidently has application.

Why have analytic functionalists been so complacent about this incredibly powerful argument against their view, an argument which – on the assumption that they took a philosophy degree – they cannot possibly have been ignorant of? I think that straightforward analytic functionalists have felt unthreatened by Cartesian considerations because their view entails that the mental is multiply realized and allows that in certain non-actual scenarios the mental may be realized by non-physical goings-on. Whilst functional states in the actual scenario may be realized by fleshly mechanisms, in non-actual scenarios they are realized by ectoplasm. Therefore, the fact that we can conceive of mental processes without physical processes – as we do at the end of the second meditation – is consistent with straightforward analytic functionalism.

However, whilst it is true that straightforward analytic functionalism is consistent with the conceivability of minds without brains, it is not true that straightforward analytic functionalism is consistent with the scenario we finish up conceiving of at the end of the second meditation. The thing we end up conceiving of at the end of the second meditation is not just a thing with mentality not realized in physical stuff; it is a thing with mentality not realized in any stuff. And it is not coherent to suppose that ‘the higher-order state of having some other state that plays the pain role’ exists in the absence of some other state that plays the pain role.

The Australian analytic functionalist avoids this problem by identifying pain with the realizer of the pain role rather than with the pain role itself. It is then conceivable that pain is a fundamental state, as there are scenarios where a fundamental state plays the pain role in the population being considered. Furthermore, there are coherent scenarios in which pain does not play the pain role. In cases of what Lewis calls ‘mad pain’, there is an individual who instantiates the state which plays the pain role in her population, without it being the case that...

Table of contents

• Cover
• Title
• Part I   Metaphysics of Mind
• Part II  Mind and Cognitive Science
• Index