Substance Dualism Refuted?
Channel: Gary Edwards
Date: 2013-07-31

A critical analysis of substance dualism. This video is a companion piece to this one: http://www.youtube.com/watch?v=iVbG90kr1B0

(1) Transcript
(2) LInks

(1) Transcript:

There are very few serious thinkers who advocate substance dualism these days. There are though alas, a few zealots who still allow their enthusiasm for what they think it promises to get the better of their reason. This video, which shall be my last on the subject, is my final appeal to their latent capacity for logical thought.

This is a metaphysical substance.

 As such, it's the simplest and most durable thing under consideration. It has the fewest parts of all the things we are thinking about at any particular time, whilst also being the least vulnerable to change .

Substance dualism is the claim that there are two such substances. In order for substance dualism to be true, both (A) and (B) must be a substance. If only one, or neither, of them is the simplest and most durable thing under consideration, then substance dualism is false.

When mind and matter are said to be distinct substances, it follows, if there's some kind of causal relationship between them, that a causal relationship between two substances is being proposed. 
 
When any two things are in a causal relationship, both of them are under consideration. Causal relations inevitably draw both 'relata' -- that which causes, and that which is effected -- into our thoughts.

When those two things are substances there are a limited number of consequent scenarios.

Firstly, regarding simplicity, either (A) is simpler than (B), (A) and (B) are equally complex, or (B) is simpler than (A). 

However:

If (A) is simpler than (B), then (B) is not the  simplest thing under consideration, and substance dualism is false. 

If (A) and (B) are equally complex, then neither is the simplest thing under consideration and substance dualism is false. 

If (B) is simpler than (A), then (A) is not the simplest thing under consideration and substance dualism is false.

The requirement for simplicity therefore falsifies substance dualism given the demands of causal interaction.

Secondly, regarding durability, either (A) can cause changes in (B), (A) and (B) can cause changes in each other, or (B) can cause changes in (A). 

However:

 If (A) can cause changes in (B), then (B) is not the most durable thing under consideration and substance dualism is false

If (A) and (B) can cause changes in each other, then neither (A) nor (B) is the most durable thing under consideration and substance dualism is false.

If (B) can cause changes in (A), then (A) is not the most durable thing under consideration and substance dualism is false.

So the requirement for durability also falsifies substance dualism given the demands of causal interaction.

It follows then, if we accept that there are causal relations between mind and matter, that mind/matter substance dualism is refuted and that any preference for it is irrational.



Thank you for listening.


(2) Links

On ontological substance:

    http://plato.stanford.edu/entries/substance/

    http://www.iep.utm.edu/substanc/

On causation:

    http://plato.stanford.edu/entries/causation-metaphysics/

    http://www.iep.utm.edu/mental-c/

On Elisabeth of the Palatinate:

https://en.wikipedia.org/wiki/Elisabeth_of_the_Palatinate