1.1 What is Philosophy of Mind?
The Philosophy of Mind investigates concepts relating to the mind and consciousness as a whole as well as individual mental phenomena, such as thoughts, desires, beliefs, intentions, feelings and perception. What is the nature of mind and mental phenomena? What is consciousness?
Humans have minds. Stones do not. Where does this difference come from? Humans are alive and stones are not. Plants are alive, too, but they do not have minds. Some animals have a mind in as much as they can be tired, hungry, happy, excited or in pain. Maybe others, like insects, do not have minds. Mental phenomena are closely connected to behaviour. To have a mind, the behaviour of a creature must be sufficiently complex. The more complex the creature, the more complex its mental life. But there must be more to mental phenomena than just behaving in a certain way, otherwise how could you ever hide your thoughts?
For much of humanity’s existence, people believed that the soul is the seat of thoughts, emotions and consciousness. Combine a general scientific outlook with advances in neuroscience and it is tempting to say that the mind is just the brain.
Suppose you are in a natural history museum looking at a scene depicting how humans lived 10,000 years ago. One of those early humans looks a bit pensive, and someone says: she’s trying to figure out if it’s possible to square the circle. That’d be a joke. But why does it not make sense to assume an early human is thinking about a fairly advanced problem of geometry? The earliest members of the species homo sapiens had very much the same brain as we do. If thoughts are just states of your brain, why shouldn’t an early human just happened to have the brain states that would constitute thinking about squaring the circle? Maybe this shows that mental states are not just states of the brain, but their content also depends on the environment someone inhabits.
I'll often talk about mental events and mental states. The former suggest a happening in the mind, such as having an idea, feeling a sudden pain, gaining an insight, losing the plot. The latter suggest something more constant, like having a toothache, believing to have lost your phone, knowing the way to Larissa. I won't draw a distinction between events and states. Maybe a state is an event that stays static for a while, or an event is a state of change.
It may turn out that mental events and properties are special kinds of physical events and properties. Then there is no principled distinction between the mental and the physical. However, we could still draw a distinction between those physical events that are also mental events and those that are not. Merely physical phenomena are those that are not also mental. They may turn out to encompass the entire physical realm, if the mind turns out to be non-physical.
We must resist the temptation to say that in case mental states are just physical states they are somehow ‘unreal’ or do not really exist. Quite to the contrary: if mental states are identical to states of the brain, they are just as real as your brain is.
No matter what the nature of the mind is, there are correlations between mental states and physical states. Something in your body changes, suddenly you are awake, and you feel thirsty or hungry. You decide to get up and go to the fridge, and your body is set in motion. Many people agree that the mental supervenes on the physical: there are no changes in mental states unless there are changes in physical states, for instance in the brain. But not conversely: all kinds of things may change in your brain, while you continue to be hungry or thirsty or to have the same thoughts. Thus having different mental states means being in different physical states, and being in same physical states means having the same mental states.
There are many ways of defining supervenience. ‘Supervenience’ is derived from the Latin supervenire, ‘to arrive on the scene’ or ‘to arrive in addition’. If A supervenes on B, then A arrives on the scene in addition to B. A fairly loose way of characterising the supervenience of the mental on the physical is that if something has a mental property, it must also have some physical property in virtue of which it has the mental property, i.e. whatever has this physical property also has this mental property. In other words, something cannot simply have a mental property: the mental property must always be ‘grounded’ in some physical property, and there is a systematic relation between the two. Another idea is that A supervenes on B, if, whenever A changes, B changes, while B may change without A changing. Alternatively, we can say that a change in A necessitates a change in B, but it is possible that B changes without A changing. A change in B is a necessary condition for a change in A, but it is not a sufficient condition. What exactly this means very much depends on the modality involved in the definition. Is it just a statement of what is the case as a matter of fact? Is it physical or biological necessity and possibility? Metaphysical necessity and possibility? Something different altogether?
The concept of supervenience is used also in other areas of philosophy. For instance, if it is not possible that of two physically indistinguishable actions one is good, right or just and the other bad, wrong or unjust, then ethical properties of actions supervene on their physical properties. On the other hand, maybe if there are genuine moral dilemmas, then they don’t. Another example, if of two physically indistinguishable artefacts it is not possible for one to be beautiful or harmonious, the other unharmonious or ugly, then aesthetic properties of objects supervene on their physical ones. On the other hand, the historic significance of an object of art presumably does not supervene on the physical properties intrinsic to the object, but it needs to be taken into account who made it. Even if there is a physically indistinguishable copy of Michelangelo’s David, it wouldn’t have the same historical significance as the original.
1.3 The Mind-Body Problem
There is a widely shared impression that mental phenomena are radically different from merely physical ones. This gives rise to the mind-body problem. No matter how different the mental is from the merely physical, creatures with a mind like humans and some animals inhabit a physical universe. Creatures with a mind are very different from things which do not have a mind. How does this difference between the mental and the merely physical arise? How can there be such things apparently so different from merely physical objects in a physical universe?
Even though the realm of the mental seems to be unlike anything in the merely physical world, nonetheless both stand in direct relations with each other. The world is to some extent subject to our will: we can cause things to happen. I have a desire and know how to satisfy it. I decide to proceed into action. My body, a merely physical thing, is set into motion in accordance with my decision. Suppose you have a headache and you are in a bad mood. You take an aspirin, the headache abates, and you are in a better mood. It might not appear to be such a grand problem how a headache can be cured by aspirin: some chemical reactions (in the brain or elsewhere) are responsible for the headache, and the aspirin counteracts them. But how can this chemical process affect your mood?
If there are minds which are to be strictly distinguished from our body, then how does the mind interact with the physical world?
If minds are not special in this sense, then how come creatures with a mind differ so significantly from merely physical objects?
Crane, T. Elements of Mind (Oxford: Oxford University Press, 2001)
Heil, J. Philosophy of Mind: A Contemporary Introduction (London, New York: Routledge, 2013)
Kim, J. Introduction to the Philosophy of Mind (Boulder, CO: Westview 2010)
Entries in the Stanford Encyclopaedia of Philosophy
Beakley, B. and Ludlow, P. (eds.) The Philosophy of Mind: Classical Problems/Contemporary Issues (Cambridge, MA: MIT Press, 2006)
Heil, J. (ed.) Philosophy of Mind: A Guide and Anthology (Oxford: Oxford University Press, 2004)
Rosenthal, D.M. (ed.) The Nature of Mind (Oxford: Oxford University Press, 1991)