Everyone’s auditory system, apparently, makes noise, but the question remains, is it always audible to oneself? If so—if the auditory faculty comes down to a version of Heisenberg’s uncertainty principle, whereby the act of hearing in itself changes what can be heard—then my search is over. Silence cannot be because within the instruments through which I must measure it, a total absence of sound cannot exist.

George Michelsen Foy, Zero Decibels, loc. 526