Page 96 - Darwin's Dilemma: The Soul

Darwin’s Dilemma: The Soul

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The hearing process is similar to seeing. The information
reaching us as sound is, just like images, merely electrical signals.
The external ear collects the sound waves around us and transmits
them to the middle ear. This then reinforces the vibrations and for-
wards them to the inner ear, which then converts these vibrations
into electrical signals, depending on their frequency and concen-
tration, and sends them to the brain.
In the brain, these messages are sent to the hearing center
where they are processed and analyzed. And that is how hearing
takes place.
However, one very important point here is that just as with
images, the sounds we heard are not somewhere outside our
brains. Peter Russell, known especially for his work on human con-
sciousness, describes the position:
The same is true of sound. When Bishop Berkeley argued that noth-
ing exists apart from our perceptions, a vigorous debate ensued as to
whether a falling tree made a sound if no one was there to hear it. At
that time nothing was known of how sound was transmitted
through the air, or how the ear and brain functioned. Today we
know much more about the processes involved, and the answer is
clearly “No.” There is no sound in physical reality, simply pressure
waves in the air. Sound exists only as an experience in the mind of a
perceiver—whether that perceiver is a human being, a deer, a bird,
or an ant. 58
For us, external sound exists only for so long as we perceive
it. However, to repeat a very significant point, sounds, like visual
images, are not inside our brains. In our brains, all that exists is
electrical signals. All the kinds of sound we regard as “real” are
products of these electrical signals in the brain. When we chat
with a friend, we perceive their three-dimensional image in
a perfect form in our visual cortex; we also hear the

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