Page 159 - Allah is Known through Reason

HOW DO WE SEE, HEAR, AND TASTE?
The act of seeing is realised progressively. Light clusters (photons) trav-
el from the object to the eye and pass through the lens at the front of the
eye where they are refracted and fall upside-down on the retina at the back
of the eye. Here, impinging light is turned into electrical signals that are
transmitted by neurons to a tiny spot called the centre of vision in the back
of the brain. This electrical signal is perceived as an image in this centre in
the brain after a series of processes. The act of seeing actually takes place
in this tiny spot in the posterior part of the brain, which is pitch-dark and
completely insulated from light.
Now, let us reconsider this seemingly ordinary and unremarkable
process. When we say, "we see", we are in fact seeing the effects of
impulses reaching our eyes and induced in our brain, after they are trans-
formed into electrical signals. That is, when we say, "we see", we are
actually observing electrical signals in our mind.
All the images we view in our lives are formed in our centre of vision,
which only comprises a few cubic centimetres of the volume of the brain.
Both the book you are now reading and the boundless landscape you see
when you gaze at the horizon fit into this tiny space. Another point that
has to be kept in mind is that, as we have noted before, the brain is insu-
lated from light; its inside is absolutely dark. The brain has no contact with
light itself.
We can explain this interesting situation with an example. Let us sup-
pose that in front of us there is a burning candle. We can sit opposite this
candle and watch it at length. However, during this period, our brain never
has any direct contact with the original light of the candle. Even as we see
the light of the candle, the inside of our brain is completely dark. We watch
a colourful and bright world inside our dark brain.
R. L. Gregory gives the following explanation about the miraculous
aspects of seeing, something that we take so much for granted:
We are so familiar with seeing, that it takes a leap of imagination to realise
that there are problems to be solved. But consider it. We are given tiny dis-
torted upside-down images in the eyes, and we see separate solid objects in
surrounding space. From the patterns of simulation on the retinas we per-

A Very Different Approach to Matter 159