1. Plato, Aristotle and Descartes on body and soul
Michael Lacewing

2. Plato’s Phaedo Death is the separation of the soul from the body
When it is joined to a body, “the soul is only able to view existence through the bars of a prison, and not in her own nature; she is wallowing in the mire of all ignorance”

3. A separate soul I Souls can’t be destroyed
The soul is unseen
All unseen things are ‘simple’, they have no parts
To destroy something is to break it into parts
Objection: perhaps there are other types of destruction

4. A separate soul II
Change is change from what something (currently) is to what it (currently) is not
Life changes into not-life, death
Becoming alive involves a change from not being alive
Upon life, the soul is joined to the body - so the soul exists before birth
Objection: not all change is like this - coming into existence is not a change into an opposite

5. Aristotle A person is an ‘ensouled body’
The soul is the ‘form’ of the living body - what does this mean?
Four types of ‘cause’ or explanation
Material: ‘that out of which a thing comes to be, and which persists’, e.g. marble of a sculpture
Efficient: brings about change or rest, e.g. the sculptor

6. Four causes (cont.)
Final: ‘the end (telos), that for which a thing is done’, e.g. the answer to why the sculptor made the statue
Formal: ‘the account of the essence’, e.g. what a ‘sculpture’ is, so that we understand what the sculptor was doing

7. What is a heart? Material: muscle (flesh) Formal: pumps blood
Final: sustain life by pumping blood
Efficient: cell development guided by genes aiming at creating a living organism

8. What is a soul?
‘living is the being [the essence] of living things, and the soul is the cause and principle of this.’ (415b).
What it is to be a living being is to live; and the soul is the formal, efficient and final cause of a living thing.

9. What is a soul?
Final: living things live in order to live (stay alive)
Efficient: living changes and develops our bodies; it changes and develops us as persons
Formal: the activity of living provides an account of what it is to be what we are, a particular kind of living being.

10. Soul as form
Matter endures (material cause). But we always identify matter by some form it has.
With living beings, matter constantly changes. Living things are forms embodied in ever-changing matter. Even to refer to a ‘living thing’ is to privilege form over matter.

11. Human soul and body
Different living things are capable of different kinds of lives:
plants: growth and reproduction;
animals: sensation;
human beings: rational activity
So each has a corresponding type of soul.

12. The intellect No part of the body corresponds to the intellect
Each sense is limited to a type of experience
But thought can be about anything
So the intellect ‘seems to be another kind of soul, and this alone admits of being separated, as that which is eternal from that which is perishable’ (428b)

13. Descartes on the soul
Aquinas developed Aristotle’s ideas, claiming the soul, intellect and the form were the same thing, and a separable substance
Descartes agrees, but drops reference to ‘form’: The soul is the intellect and a separate substance from the body.
Bodies work mechanically - they don’t need explaining in terms of the soul.

14. What am ‘I’?: the narrow view
‘I’ am essentially a soul, a thing that thinks that can be separated from a body. (Meditation II)
But is Descartes right to think souls can be separated from bodies?

15. What am I?: the broad view
‘I am not only lodged in my body as a pilot in a vessel, but…I am very closely united with it, and so to speak so intermingled with it that I seem to compose with it one whole.’ (Meditation VI)
I am a person - an embodied soul.
the soul takes on bodily experiences as its own, i.e. we refer our sensations, emotions, etc. to our selves.

16. What am I? essentially
I am not essentially a person, because I could be the same ‘thing’ - a soul - without a body.
I am essentially a person, since I am my psychological properties, and these depend on my body.
I am essentially a person, because the unity of soul and body creates a new, distinct kind of thing.