Each of the examples given by the materialists in reply to the fact
that matter is a perception shows how far removed they are from comprehending the subject.
Another example of this is a materialist view that accepts that the external world is
perceived in the brain as an image but then divides the images into two categories: images
having material correlates and those that do not. This view then claims that the images in
the brain have material correlates.
What is the scientific evidence of the claim that the images in the
brain have correlates in the external world?
There is no scientific evidence for this. No one has any knowledge or
evidence about the outside of the brain. Everything a human being sees and perceives
exists in the brain as images. It is impossible to know whether there is anything outside
the brain by relying on the images inside the brain. Therefore, the claim of this
materialist that "the images in the brain have physical correlates" is merely a
futile allegation. It is impossible for him to put forward any scientific evidence to
prove this allegation.
The materialist writer answers this point by saying "I do not know
whether the images in my brain have correlates in the external world or not but the same
thing applies when I speak on the phone. When I speak on the telephone, I cannot see the
person I am speaking to but I can have this conversation confirmed when I later see him
face to face".
By saying so, this writer actually means the following: if we doubt our
perceptions, we can look at the matter itself and check its reality. However, it is
impossible for us to reach the matter itself. We can never get out of our mind and know
what is "outside".
Whether the voice on the phone has a correlate or not can be confirmed
by the person on the phone. However, this confirmation is also imagery experienced by the
mind. Conceding that everything is perceived in the brain but assuming that the
confirmation stage is independent of this reveals how limited is the perceptive capacity
of the person and shows that he does not understand this concept at all. However, this
logic is easily captured by a healthy person with a normal level of understanding. Each
unbiased person would know, in relation to all that we have said, that it is not possible
for him to test the existence of the external world with his senses. No one with common
sense would claim that events occur in his brain up to a certain point, but that they
afterwards go on to occur somewhere else other than his brain. By whom, then, will he
confirm whether the images in his brain have correlates or not? To the shadow beings in
his brain again? Without doubt it is impossible for materialists to find a source of
information that can yield data concerning the outside of the brain and confirm it.