Mind-Body DualismMind-Body Dualism

The Mind-Body ProblemThe Mind-Body ProblemThe problem of

explaining how a mind is connected to and interacts with a body whose mind it is, or the problem of explaining how a body is connected to and interacts with a mind whose body it is.

Monism vs DualismMonism vs Dualism

Monism - the belief that the world is made up of only one substance – physical or mental, but not both (P ≢M !)

The two branches: Materialism (physicalism) – only physical things existIdealism – the only thing that exists are minds and perceptions

Materialism vs DualismMaterialism vs DualismMaterialism is the theory that our

minds are inseparable from our bodies.

Dualism is the theory that there exists both bodies and minds, distinct from one another but linked together in some way

DualsimDualsim… is usually adopted on the

grounds that it must be true, and rejected on the grounds that it can’t be true.

Thomas Nagel

3 Minute Pause3 Minute PauseThings to think about…What is the mind-body problem?What are the two main divisions?What does Thomas Nagel mean when he says that ..dualism is usually adopted on the grounds that it must be true, and rejected on the grounds that it can’t be true. ?

Philosophy and DualismPhilosophy and Dualism In philosophy dualism is a set of views about

the relationship between mind and matter, which begins with the claim that mental phenomena, are in some respects, non physical

Minds and bodies are often supposed to be very different kinds of thing: bodies are physical or material and minds are mental or immaterial. Minds and bodies are supposed to have very different properties. For instance, bodies occupy space and have weight, but minds do not. Minds have ideas, feelings, and can dream, but not bodies.

Plato and FormsPlato and Forms

Plato’s theory of forms sees forms as distinct and immaterial substances of which the objects and other phenomena that we perceive in the world are nothing more than mere shadows

Forms are universal concepts (or ideas) which make all of the phenomenal world intelligible (allegory of the cave) Plato's Allegory of the Cave (3D Animation).mp4

In order for the intellect (the most important aspect of the mind in philosophy up until Descartes) to have access to any kind of knowledge with regard to any aspect of the universe, it must necessarily be a non-physical, immaterial entity (or property of some such entity) itself

Descartes – Substance Descartes – Substance dualismdualism

A generally well known version of dualism is attributed to René Descartes (1641), which holds that the mind is a nonphysical substance. Descartes was the first to clearly identify the mind with consciousness and self-awareness and to distinguish this from the brain, which was the seat of intelligence. Hence, he was the first to formulate the mind-body problem in the form in which it exists today.

Descartes – Descartes – Cogito Ergo Sum… Cogito Ergo Sum… The Argument from DoubtThe Argument from Doubt

“I think, therefore I am”Descartes discovered that

he could doubt whether he had a body but he could not doubt whether he had a mind

I can doubt that my body exists.

I cannot doubt that I exist,

therefore, I am not identical with my body.

Therefore, the mind is a substance distinct from the body, a substance whose essence is thought

The argument from The argument from irreducibilityirreducibility

1. Mental activities such as reason, intuition language use and subjective experience cannot be reduced to physical explanations

2. Things either have a physical or mental explanation

3. There must be non-physical explanations for these activities.

3 minute pause3 minute pauseWhy is Descartes a ‘substance’

dualist?What is the ‘argument from

doubt’?What is the ‘argument from

irreducibility’?Why might dualism fit readily

into a religious view of the world?

Cartesian DualismCartesian Dualism Cartesian dualism states that the

immaterial mind and the material body, while being ontologically distinct substances, causally interact

Mental events cause physical events, and vice-versa. But this leads to a substantial problem for Cartesian dualism: How can an immaterial mind cause anything in a material body, and vice-versa? This has often been called the "problem of interactionism".

Descartes himself struggled to come up with a feasible answer to this problem. He suggested that animal spirits interacted with the body through the pineal gland, a small gland in the centre of the brain, between the two hemispheres.

Substance vs PropertySubstance vs PropertyTwo main varieties of dualism:Substance dualism: mind is

distinct from the body (what we have been looking at so far); and

Property dualism: the mind is property of the body – this is meant to be a compromise between dualism and materialism (more about this later…)

Materialism (Physicalism)Materialism (Physicalism)Materialism (or

Physicalism) does not accept that there is a separate part of the body called the ‘soul’. An individual is a living physical body and nothing more

Materialists believe an action is the result of a chain of events, and eventually science will be able to explain everything. Music is nothing but a set of vibrations in the air, a painting is nothing more than dots on a canvas, just like a person is nothing more than a brain attached to a body with a nervous system

Emotional response, such as love or hate, is nothing more than a chemical reaction in our brain

There is no distinction therefore, between body and soul

3 minute pause3 minute pauseWhat problem arises from

Cartesian dualism?How did Descartes address this?What is physicalism?Why might physicalism fit readily

into a scientific view of the world?

Property DualismProperty Dualism Like materialism, it holds that there is only one type

of substance: physical. Property dualism denies the existence of immaterial minds that somehow interact with the physical world, animating unconscious bodies

Where property dualism parts with materialism is that it does not attempt to reduce mental states to physical states. Mental states, according to the property dualist, are irreducible; there is no purely physical analysis of mind

Property dualism thus holds that although there is only one type of substance--physical--there are two types of property--physical and non-physical. Our bodies have physical properties such weight and height, and mental properties such as beliefs and desires

This position is intended to combine the plausible aspects of both dualism and materialism, while avoiding the problems of each

Thomas Nagel Thomas Nagel – – What is it like to be a bat? (1974)What is it like to be a bat? (1974)

1. Bats have experience (i.e. there is something like ‘being a bat’)

2. Human beings are restricted to the resources of their own minds

3. Therefore, human beings cannot feel what it is like to be a bat

The above argument seeks to highlight the exclusivity of subjective experience. Nagel concludes that subjective experience is inexplicable in terms of its purpose, content of thought, or any causal relationship. A physicalist analysis is inadequate in explaining subjective experience. However, since the mental and the physical exhibit different attributes, they should be considered as distinct.

3 minute pause3 minute pauseWhat is property dualism?Does it solve any problems?

Bundle theoriesBundle theories

Bundle theorists:( e.g. David Hume, Derek Parfit)Deny the existence of a ‘self’ – instead…When we talk of ‘personhood’ we are not talking about a unified whole, but a changing collection of thoughts, sensations and experiences.Buddhism: likens the mistaken belief in self, to someone who believes that a carriage exists, in addition to its parts.Susan Blackmore:Is the belief in personality an evolutionary trick – beneficial to survival?

IdealismIdealismOpposed to both materialism and dualism is

idealismAll reality consists of mind or is mental. There is

no such thing as matter. What we commonly think of as being material objects, such as tables, trees, and our own bodies are not really physical, but are mental

This view held by George Berkeley (1685-1753), who maintained that reality consists of minds and their ideas. For Berkeley, an ordinary external world object like a table is a cluster of ideas necessarily related to some mind which is aware of them

Idealism is also known as ‘immaterialism’