Substance dualism
- Minds exist and are not identical to bodies or parts of bodies.
Key points of substance dualism –
The mind and the body are two distinct substances. So, neither
relies on the other in order to exist. Substances possess properties
so there are also mental properties and physical properties. These 2
substances causally interact with each other – you don’t feel as if
you are distinct from your body, you feel like an extension of the
body through you mind.
Two key arguments for substance dualism: indivisibility argument
and the conceivability argument.
The indivisibility argument:
The body is spatially extended, whereas the mind is not. The mind
is not extended. Descartes then draws the conclusion that the body
is divisible, and the mind is not. The idea that you cannot divide the
mind comes from introspection – when you look into your mind, you
cannot detect many parts, it all feels as though it is one.
Given Leibniz’s law of the indiscernibility of identicals, 2 things that
have different properties cannot be identical substances.
P1. The body is divisible. Eg you could cut off your leg.
P2. The mind is indivisible. Eg on introspection, you feel as though
you are all one mind, there are no compartments involved.
C. Therefore, using Leibniz’s law, mind and body cannot be the
same thing.
Put another way:
The mind is indivisible, for example, when you introspect, you
appear to experience your mind as one whole. Whereas, you
experience the body as being in parts, if you amputate your leg,
the body is in parts, or even if an eyelash fell out. They
subsequently have different properties. Leibniz’s law of the
indiscernibility of identicals, states that no two substances with
differing properties can be identical. As such, mind and body are
distinct substances because they hold at least one different
property.
Responses to this argument –
THE MENTAL IS DIVISIBLE IN SOME SENSE -
You could say that instances such as personality disorders could
suggest that you can divide the mind. Sometimes some parts seem
not to be able to communicate with other parts. Also, people may
believe and desire one thing consciously, but another thing
subconsciously. Split brain patients could be described as having
- Minds exist and are not identical to bodies or parts of bodies.
Key points of substance dualism –
The mind and the body are two distinct substances. So, neither
relies on the other in order to exist. Substances possess properties
so there are also mental properties and physical properties. These 2
substances causally interact with each other – you don’t feel as if
you are distinct from your body, you feel like an extension of the
body through you mind.
Two key arguments for substance dualism: indivisibility argument
and the conceivability argument.
The indivisibility argument:
The body is spatially extended, whereas the mind is not. The mind
is not extended. Descartes then draws the conclusion that the body
is divisible, and the mind is not. The idea that you cannot divide the
mind comes from introspection – when you look into your mind, you
cannot detect many parts, it all feels as though it is one.
Given Leibniz’s law of the indiscernibility of identicals, 2 things that
have different properties cannot be identical substances.
P1. The body is divisible. Eg you could cut off your leg.
P2. The mind is indivisible. Eg on introspection, you feel as though
you are all one mind, there are no compartments involved.
C. Therefore, using Leibniz’s law, mind and body cannot be the
same thing.
Put another way:
The mind is indivisible, for example, when you introspect, you
appear to experience your mind as one whole. Whereas, you
experience the body as being in parts, if you amputate your leg,
the body is in parts, or even if an eyelash fell out. They
subsequently have different properties. Leibniz’s law of the
indiscernibility of identicals, states that no two substances with
differing properties can be identical. As such, mind and body are
distinct substances because they hold at least one different
property.
Responses to this argument –
THE MENTAL IS DIVISIBLE IN SOME SENSE -
You could say that instances such as personality disorders could
suggest that you can divide the mind. Sometimes some parts seem
not to be able to communicate with other parts. Also, people may
believe and desire one thing consciously, but another thing
subconsciously. Split brain patients could be described as having
