Musical scales are exponential as well. (octaves are frequency doublings) There's also this experimental evidence about sensing loudness, weight, vibration, lig

Musical scales are exponential as well. (octaves are frequency doublings) There's also this experimental evidence about sensing loudness, weight, vibration, lightness, saltiness, thickness and several dozen other things. From: http://en.wikipedia.org/wiki/Stevens%27_power_law http://en.wikipedia.org/wiki/Stevens%27_power_law ... The general form of the law is ψ(I) = kI^a where I is the magnitude of the physical stimulus, ψ(I) is the psychophysical function relating to the subjective magnitude of the sensation evoked by the stimulus, a is an exponent that depends on the type of stimulation and k is a proportionality constant that depends on the type of stimulation and the units used.