Substance Dualism

Substance dualism

The mind and body are two distinct and independent substances (mind being non-physical and non-extended and body being physical and extended) that are merely contingently connected

Substance

* A bearer of properties but not itself property dependent on anything
* For example eg wax from a beehive tastes sweet and looks yellow, if you melt it, it loses its former properties, but it is still wax

Property

- Doesn't have the capacity to exist independently

Mind without body is inconceivable

The statement "Mind without body is inconceivable" challenges Descartes' assertion that he can conceive of mind and body as separate substances. This challenge suggests that our ability to conceive of something depends on our knowledge, and that Descartes may have lacked knowledge about the physical nature of the mind. Our current understanding of the brain suggests that the mind is fundamentally a physical part of the body, and therefore it may be reasonable to insist that we cannot conceive of the mind existing without the body.

What is conceivable may not be possible

This inference is highly questionable as conceivability is not always a reliable guide to possibility. The argument can be demonstrated using a counter-example where something can be conceived but is impossible, indicating that the ability to conceive of mind existing without body does not suggest that it is possible.

Contingent connection

* A contingent connection is one that happens to hold but does not have to
* Eg fish and chips are often thought of as one meal and can be thought of as being contingently connected

Descartes Dualism

* Interactionist dualist - he believes that the mind and body exist in a causal relation
* We have private and privileged 1st person access to our own minds
* My awareness of my own mind is infallible and incorrigible
* Our bodies are public and knowable in the 3rd person.
* Our knowledge of our bodies is not infallible, and statements about our bodies not incorrigible

Descartes' Conceivability Argument

i) I have a clear and distinct idea of myself as something that thinks and is not extended in space and I also have a clear and distinct idea of body as something that is extended and does not think

(ii) Anything that can be clearly and distinctly conceived is possible - so the existence of mind and body as distinct substances is possible

(iii) Therefore, mind and body are two distinct substances

What is conceivable may not be possible (MASKED MAN)

* It is not obviously true that conceivability is a reliable guide to possibility
* Masked man example
* I was able to conceive something impossible (that the masked man is not my father), yet the fact that it is conceivable doesn't mean it is possible
* We can doubt the conceivability is really a guide to possibility and should conclude that Descartes' ability to conceive of mind existing without body does not suggest that this is possible

* Masked man example

I believe that the masked man robbed the bank. At the same time, I believe that my father did not rob the bank. Clearly, I can conceive that the masked man is not my father. Now, whoever the masked man is, it is impossible that he is someone else - if he is not my father then it's impossible that he is my father, and if he is my father then it is impossible that he is not. Father turns out to be the masked man who robbed the bank.