This weekend my son asked me, “Dad, what is ‘sound’?” I replied, “Well, interestingly, sound does not really exist.” Then we had a really fun one hour conversation about why this is so. Most readers will know exactly why this is true but in case some don’t follow me, let me offer this condensed explanation:
- When matter oscillates, its momentum can be transferred through surrounding medium via pressure waves.
- When these pressure waves, after possibly many interim alterations, finally reach the human ear
- These pressure waves then move the human ear drum and the anatomical mechanism in the inner ear converts the ear drum’s motions (note: “motions”, not “sound”) into electrical impulses.
- The well-working human brain then converts these electrical signals into a perception of sound.
- Thus: oscillation –> pressure wave –> ear drum movement –> electrical impulse –> brain –> perception/illusion of sound
- Why “illusion”? Well, there is no reason the same electrical signals in the nervous system could not be converted to tastes, vision, kinesthetic sensations or even emotions. Indeed, some people have this sort of brain anomaly (synesthetes). It is all a translation issue of one sort of information into another.
So “sound” is a human contrivance — at a biological level. Likewise, so is beauty. Sure, on a relativistic level, sound is very real, of course. But sometimes taking our relative perceptions too seriously can take us off guard and sting us. Holding them lightly is a valuable practice. And thus, my conversation with my son. After this heavy conversation we had a great time playing some music together — relativistic bliss !
One of my favorite related posts: Truth and Beauty: deceptive abstractions