5 A* Metaphysics of Mind philosophy essays
1. Dualism
2. Behaviourism
3. Mind-brain type identity theory
4. Eliminative materialism
5. Functionalism
, Are dualists right to say that minds and their properties are non-physical? (25 marks)
Dualists claim that the mind and body are not identical substances/ properties, and the mental
cannot be reduced to the physical. In this essay it will be argues that mins and their properties are
not non-physical.
Descartes argues that the mind and body must be separate substances are they have different
properties in his indivisibility argument however this fails to prove dualism as it is logically possible
for mental and physical states to have the same properties. Descartes indivisibility argument goes as
follows:
P1: My mind is indivisible
P2: My body is divisible
P3: Leibniz’s law: if an object has a property another lacks, then they must be
different objects
C: Therefore, my mind is not my body
This argument does have a weight as Leibniz law is a valid principle, viewed as an intuitive and self-
evident law of logical. However, there is evidence to support that the mind is divisible, and that the
body is indivisible which means that the mind and body may not have different properties and so not
separate substances. An epilepsy surgery, corpus callosotomy, where the nerve fibres between the
two hemispheres of the brain are cut, can lead to two separate consciousness in the brain. Not only
does this suggest that the mind and brain are interconnected as a change in the brain is reflected in
the mind, but also, that as consciousness can be divided and therefore the mind can. Furthermore, it
is possible that there will be a point in dividing subatomic particles where something cannot be
divided which would mean that “dividing” the body would be merely moving atoms. Therefore, not
everything that is indivisible is non-physical. Although these criticisms cannot be proof that
Descartes argument is flawed, the evidential and logical possibilities of the mind being divisible, and
the body indivisible means that Descartes is wrong to use divisibility as a distinguishing factor
between the mind and body, so he does not prove that the mind and body are separate substances.
A less effective argument from Descartes for substance dualism is his conceivability argument
because the conceivability of two things separately tells us nothing about the state of those things in
the actual world. Descartes argues that:
P1: If I can conceive of the essential natures of two things separately, it must be
possible to separate them
P2: I perceive myself (my mind) to be essentially a thinking thing and an unextended
thing
P3: I perceive my body to be essentially an extended and unthinking thing
C: It must be possible for mind and body to be separated in reality, meaning that
they are difference substances
The first weakness in Descartes argument is that conceiving the mind and body as separate
substances may not be possible. Descartes claims that the mind and body are independently existing
substances, however the issue lies with the connection between the mind and body in reality as the
mind appears to be dependent on the body for its experience and existence in the world. This means
that it may be possible to conceive of the mind and body as separate entities in the hypothetical, but
we cannot do that in the reality. Furthermore, Descartes is guilty of the masked man fallacy. the
masked man fallacy is an error in reasoning where a possibility or identity is incorrectly inferred
based on conceivability. For example, you know your friend has blue eyes, a masked man walks in
where you cannot see his eye colour, so we are not aware of him having blue eyes, you conclude
that the man is not your friend, but this is an error. With application to Descartes, he ignored the
possibility that the mind and body, as he conceives them, might not correspond to actual
1. Dualism
2. Behaviourism
3. Mind-brain type identity theory
4. Eliminative materialism
5. Functionalism
, Are dualists right to say that minds and their properties are non-physical? (25 marks)
Dualists claim that the mind and body are not identical substances/ properties, and the mental
cannot be reduced to the physical. In this essay it will be argues that mins and their properties are
not non-physical.
Descartes argues that the mind and body must be separate substances are they have different
properties in his indivisibility argument however this fails to prove dualism as it is logically possible
for mental and physical states to have the same properties. Descartes indivisibility argument goes as
follows:
P1: My mind is indivisible
P2: My body is divisible
P3: Leibniz’s law: if an object has a property another lacks, then they must be
different objects
C: Therefore, my mind is not my body
This argument does have a weight as Leibniz law is a valid principle, viewed as an intuitive and self-
evident law of logical. However, there is evidence to support that the mind is divisible, and that the
body is indivisible which means that the mind and body may not have different properties and so not
separate substances. An epilepsy surgery, corpus callosotomy, where the nerve fibres between the
two hemispheres of the brain are cut, can lead to two separate consciousness in the brain. Not only
does this suggest that the mind and brain are interconnected as a change in the brain is reflected in
the mind, but also, that as consciousness can be divided and therefore the mind can. Furthermore, it
is possible that there will be a point in dividing subatomic particles where something cannot be
divided which would mean that “dividing” the body would be merely moving atoms. Therefore, not
everything that is indivisible is non-physical. Although these criticisms cannot be proof that
Descartes argument is flawed, the evidential and logical possibilities of the mind being divisible, and
the body indivisible means that Descartes is wrong to use divisibility as a distinguishing factor
between the mind and body, so he does not prove that the mind and body are separate substances.
A less effective argument from Descartes for substance dualism is his conceivability argument
because the conceivability of two things separately tells us nothing about the state of those things in
the actual world. Descartes argues that:
P1: If I can conceive of the essential natures of two things separately, it must be
possible to separate them
P2: I perceive myself (my mind) to be essentially a thinking thing and an unextended
thing
P3: I perceive my body to be essentially an extended and unthinking thing
C: It must be possible for mind and body to be separated in reality, meaning that
they are difference substances
The first weakness in Descartes argument is that conceiving the mind and body as separate
substances may not be possible. Descartes claims that the mind and body are independently existing
substances, however the issue lies with the connection between the mind and body in reality as the
mind appears to be dependent on the body for its experience and existence in the world. This means
that it may be possible to conceive of the mind and body as separate entities in the hypothetical, but
we cannot do that in the reality. Furthermore, Descartes is guilty of the masked man fallacy. the
masked man fallacy is an error in reasoning where a possibility or identity is incorrectly inferred
based on conceivability. For example, you know your friend has blue eyes, a masked man walks in
where you cannot see his eye colour, so we are not aware of him having blue eyes, you conclude
that the man is not your friend, but this is an error. With application to Descartes, he ignored the
possibility that the mind and body, as he conceives them, might not correspond to actual
