So, if we interpret the word ‘sound’ to mean a human experience rather than a physical phenomenon, then when there is nobody around there is a sense in which the falling tree makes no sound at all. We have no basis for our common-sense assumption that these secondary qualities reflect or represent reality as it really is. Philosophers have long argued that sound, colour, taste, smell and touch are all secondary qualities which exist only in our minds. Everything to this point is explicable in terms of physics and chemistry, but the process by which we turn electrical signals in the brain into human perception and experience in the mind remains, at present, unfathomable. The human auditory apparatus simply translates one set of physical phenomena into another, leading eventually to stimulation of those parts of the brain cortex responsible for the perception of sound. Now, to a large extent, we can interpret the actions of human sense organs in much the same way we interpret mechanical measuring devices. But sound is also a human experience, the result of physical signals delivered by human sense organs which are synthesized in the mind as a form of perception.
Here the word ‘sound’ is used to describe a physical phenomenon – the wave disturbance. If by sound we mean compressions and rarefactions in the air which result from the physical disturbances caused by the falling tree and which propagate through the air with audio frequencies, then we might not hesitate to answer in the affirmative. Of course, the answer depends on how we choose to interpret the use of the word ‘ sound’. If a tree falls in the forest, and there’s nobody around to hear, does it make a sound?įor centuries philosophers have been teasing our intellects with such questions.