An introduction to

This is a metaphysical question. The question we are asking can be paraphrased: what kind of thing is a mind? Is mind the same thing as consciousness? Probably not, but minds must be conscious.

 Réné Descartes answered this question in a way that has determined the parameters of the philosophy of mind ever since.  Prior to Descartes, philosophers believed that all living beings, all entities with an internal source of motion, had a soul:  Soul is responsible for growth and change.  Soul plays a functional role in the organism.  Soul is the organizing principle and fundamental explanation of a natural organism.

 Vegetative soul: responsible for growth (respiration, metabolism, and cellular division) and germination (production of seed and generation of offspring).  Animal soul: responsible for perception, appetite (emotions), and locomotion.  Rational soul or intellect: responsible for thought.

 Descartes and many others believed that the physical world could be entirely explained in terms of mechanical forces or direct contact between semi-rigid bodies.  On this model, the life, growth, change, and motion of plants and animals could be explained as an intricate mechanical system.

Mechanism provided a perfectly good explanation of animal and plant organisms (or so Descartes supposed), but it failed to explain thought. Why?  All material bodies are extended in space.  But thought is non-spatial.  Moreover, I can doubt the existence of spatially extended bodies, but I cannot doubt the existence of my own thought.  So, Descartes concludes, thoughts must be the attributes of some non-material substance, mind or intellect, which is truly identified with me.

 Thomas Hobbes: “M. Descartes is identifying the thing which understands with intellection, which is an act of that which understands. Or at least he is identifying the thing which understands with the intellect, which is a power of that which understands. Yet all philosophers make a distinction between a subject and its faculties and acts, i.e., between a subject and its properties and its essence: an entity is one thing, its essence another. Hence it may be that the thing that thinks is the subject to which mind, reason or intellect belong; and this subject may thus be something corporeal.” (Objections to Descartes’ Meditations, AT VII, ).  Pierre Gassendi: “… so far as I can see, the only result that follows from this is that I can obtain some knowledge of myself without knowledge of the body. But it is not yet transparently clear to me that this knowledge is complete and adequate, so as to enable me to be certain that I am not mistaken in excluding body from my essence.” (Objections to Descartes’ Meditations, AT VII, 201)

 In the 1950s and 60s J.J.C. Smart and U.T. Place proposed that “consciousness is a process of the brain.”  This is strictly analogous to saying “lightening is an electrical discharge.”

A good, naturalist, scientific explanation would tell us that lightening is identical to electrical discharge. Why should there be anything special about the mind? If we want to explain what the mind is as a natural phenomenon, naturalism tells us to look to the brain.

 Modularity of mind: what cognitive neuroscience can do is study “modules,” i.e. discrete computational systems.  Input  Processing  Output  No “in kind” reduction:  Modules are inherently plastic.  Reduction requires building bridges (explanation bridges a gap between two distinct things).

 Jerry Fodor has posited that the crucial piece that we need to understand about consciousness is the Language of the Mind.  This LOM is the “code” in which our computational processes are written.  LOM is embedded in the natural architecture of the brain, it is innate.  Cf. Noam Chomsky’s “universal grammar”

 Machinemensch, from Frtiz Lang’s Metropolis (1927)

 Functionalism claims that mental states are a result of complex sets of computational processes that happen in the brain.  Here, there still is a reductive explanation, but one that is called “token” rather than “type” reduction.  Artificial intelligence imagines that future technological achievements will allow us to create computer programs that have all the properties of consciousness.  These ideas have lead to the idea of “supervenience”: conscious is some set of properties or states (C) that supervene over physical ones (P) and P  C.

 But isn’t there something unique about the phenomenology of consciousness or what it feels like to be me that cannot be explained by science?  Zombies – is it conceivable for there to be a physical duplicate of me without any subjective experience?  Mary the Superscientist – when I see a color, isn’t that qualitative feeling (color quale) something more than just the objective, scientific explanation of the brain state I am having?

David Chalmers (The Conscious Mind: In Search of a Fundamental Theory, 1996) argues that there are “easy” problems of consciousness: explaining behavioral and cognitive functions, how they work, and how they are correlated with various mental states. But, he finds, these problems are of a different sort than the “hard problem”: Why should all this physical stuff produce phenomenal experience? Why are the lights of conscious experience on at all? What is the relationship between the subjective texture of experience and the physical processes in the world?

 The physicalist or materialist says that whatever consciousness is, it must be either a physical thing or supervene on a physical thing.  The hard problem either does not exist (eliminativism) or the explanatory bridges will be built by future neuroscientists (deflationary and reductive accounts).

Daniel Dennett: “There is no separate medium in the brain, where a content can 'appear' and thus be guaranteed a shot at consciousness. Consciousness is not like television—it is like fame. One’s 'access' to these representations is not a matter of perceiving them with some further inner sensory apparatus; one’s access is simply a matter of their being influential when they are. So consciousness is fame in the brain, or cerebral celebrity. That entails, of course, that those who claim they can imagine a being that has all these competitive activities, all the functional benefits and incidental features of such activities, in the cortex but is not conscious are simply mistaken. They can no more imagine this coherently than they can imagine a being that has all the metabolic, reproductive, and self-regulatory powers of a living thing but is not alive.” (

 Dualism contends that consciousness and mental states are some separate property or thing that cannot be reductively explained by physical facts, even all the physical facts that could ever be known about the universe.  Chalmers – property dualism  David Rosenthal – Higher Order Theory (HOT) of conscious states

 Monism claims that there is only one kind of substance in nature, but there are at least three very different positions to take here:  Consciousness is merely epiphenomenal.  The basic components of consciousness are embedded in a complete account of fundamental physics.  Naturalism is in some basic sense dependent on human consciousness for its power of explanation (Idealism).

 Some choose to ultimately reject the project of naturalistic explanation altogether in the case of consciousness.  However, some non-theological case needs to be made for this maneuver.  “New Mysterians”

 Freedom, action, and responsibility  Human identity  Personhood and the designation of ethical rights  Philosophy of Perception  Cognitive bases for knowledge  Mental Representation and Intentionality  Philosophy of Language  Cognitive Science, Neurobiology, Computer Science, Psychology