Soul, mind and body

Dualism

Plato: Knowledge from geometry

We must gain knowledge of geometry either in this life or previously

We can work out the size of a square using one side with no previous geometric knowledge

If we are able to do this, we must have learnt it either in this life or previously

As we did not learn it in this life, we must have learnt it previously

So we must have a previous life

So our soul must exist separate from our body

Analogy / quote: Slave boy

Slave boy could work out the size of a square from using one side

Weakness: Rosalyn Weiss

So he must have learnt it previously

So the soul exists separate from the body

Argues that Socrates used leading questions when questioning the slave boy (Socratic method)

So he did learn knowledge of geometry in this life

So Plato does not prove that there was a previously existing soul separate from the body

Overcoming; Forms

Socrates didn't use clever questioning to get the slave boy to do geometry

He guided the slave boy to engage in anamnesis and uncover the knowledge

So the knowledge must have been learnt previously

So our soul existed previously, separate to our body

Plato: Knowledge from opposites

Every quality comes into being from its opposite

For example, night comes from day, day comes from night

Life is the opposite of death

So if we are alive, we must have been previously dead, and the opposite

Our body does not survive death

So our soul can survive death

So our soul is separate from the body

Analogy / quote: Opposites

'The living come from the dead and the dead come from the living'

Shows how things come into existence from theit opposite

Weakness: Interaction + category mistake

Ryle argues that the soul causes effects on the body, eg. through behaviour

Non-physical things cannot cause effects on the body

So the soul must be material / physical to cause effects

So the soul is a physical entity

Overcoming: Pineal gland

Descartes argues that the problem of interaction is solved by the pineal gland

Agrees that the soul cannot cause effects on the body

Exception that the soul can control the pineal gland

So the soul can cause effects on the body

Descartes: Substance dualism

To have the ability to think, we must be aware of our existence, thoughts, and mind / soul

So we know that our soul exists

We may be deceived that our body exists, as it may be false sensations

So the body and soul must be seperate entities

Analogy / quote:

'I think, therefore I am'

Shows that if we can think, then we know that we exist

Weakness: Interaction + category mistake

Ryle argues that the soul causes effects on the body, eg. through behaviour

Non-physical things cannot cause effects on the body

So the soul must be material / physical to cause effects

So the soul is a physical entity

Overcoming: Pineal gland

Descartes argues that the problem of interaction is solved by the pineal gland

Agrees that the soul cannot cause effects on the body

Argues that the soul can control the pineal gland

So the soul can cause effects on the body

Materialism

Dawkins: Soul 2

All our behaviours are explained by our physical brain

There is no purpose for a non-physical soul to explain anything

As this explanation involves only one part explaining everything rather than multiple, it is simpler

As it is simpler, it is more likely to be true (Ockham's razor)

Descartes makes a category mistake when referring to soul as an 'individual thing' rather than a 'behaviour'

Analogy / quote: Dawkins

The mind is nothing but 'a computer made of meat'

Shows that soul is physical

Weakness: Plato

There are still things that our brain cannot explain

So there must be things that we learnt previously

For example, knowledge of geometry is learnt previously rather than in this life, and cannot be explained by the brain

So soul and body must be separate

Overcoming: Rosalyn Weiss

Argues that Socrates used leading questions when questionning the slave boy

So he did learn knowledge of geometry in this life

So Plato does not prove that there was a previously existing soul separate from the body

Ryle: Interaction + category mistake

Ryle argues that the soul causes effects on the body, eg. through behaviour

Non-physical things cannot cause effects on the body

So the soul must be material / physical to cause effects

So the soul is a physical entity

Analogy / quote: Ryle

'The ghost in the machine'

Critiquing the idea of the mind and body existing separately (dualism)

Argues that the word 'soul' falls under the category of behaviours rather than an individual thing

Plato makes a category mistake when referring to the word 'soul' as an individual thing rather than a behaviour

Weakness: Descartes

Descartes argues that the problem of interaction is solved by the pineal gland

Agrees that the soul cannot cause effects on the body

Exception that the soul can control the pineal gland

So the soul can cause effects on the body

Overcoming: Modern science

The pineal gland has been found to be responsible for the sleep cycle

So is not affected by the soul, but has its own purpose

So Descartes is wrong to assume that the soul causes effects on the physical body

Aristotle

Soul is our formal cause

The soul is the thing that makes us alive

What makes us alive is the difference between being alive and being dead

These include sets of capacities, including nous (rational thought) and phronesis (morality)

These capacities are our formal cause

So the soul is our formal cause

Analogy / quote: Wax stamp

The body and soul have a relationship like the wax and the shape of the wax

The relationship between the material and formal cause - they are seperate but inextricably linked

The material cause is the wax, and the formal cause is its shape

Weakness: Category mistake

Ryle argues that Aristotle makes a category mistake

He uses the word 'soul' as a word to describe an individual thing rather than a word to describe a behaviour

It is wrong to say the soul is the 'thing' that makes us alive, as that is putting it in the wrong logical category

Overcoming: Ryle

Ryle agrees with Aristotle that the soul is just a set of capacities

So he is not making a category mistake as he is not saying that the soul is a thing outside the body, but it is just sets of capacities

So Aristotle is right in his view of the soul being the formal cause

Soul allows us to reach eudaimonia

The soul is our and our body's formal cause

This includes sets of capacities (nous, phronesis, breathing, eating)

These sets of capacities allow us to reach our and our body's telos

So our soul allows us and our body to reach our telos, which is eudaimonia

Analogy / quote: Eye

'If the eye was a living being, the power of sight would be its soul'

The soul allows us to reach our telos

So for an eye, the power of sight allows it to reach its telos

Weakness: Sartre

Existentialists believe that 'existence precedes essence'

There is no set purpose or telos

We create this ourselves through our actions rather than it being predetermined, so we do not have a soul that allows us to reach our telos

Overcoming: variations of souls

A posteriori observations make it clear that all living things have a soul that allow them to reach their telos

For example, humans have intellectual souls, which allows us to reach eudaimonia by following virtue ethics, and plants have a vegetative soul, where their features allow them to reproduce

Supports Aristotle's view of soul allowing us to reach eudaimonia

Weakness

Plato's a priori reasoning is flawed

Cannot base the conclusion on these flawed premises, so we can reject it

For example, there is not opposite of purple

Thus, doesn't prove that our soul existed previously

Not all qualities have opposites

Overcoming

Only possible in the realm of forms, where there may exist the opposite of qualities such as purple

Thus, still plausible to conclude that our soul is separate to our body based on opposites

We are unable to gain full knowledge in the world of appearance, which has imperfect copies of the exemplars