Johnny is a man and he's bigger than you
And a very interesting thing happens to your brain, which is that any information which is common, after several repetitions, you cease to hear. You reject the common information, rather like if you gaze at something for a long time, you'll cease to really see it. You'll see any aspect of it that's changing, but the static elements you won't see ... The amount of material there is extremely limited, but the amount of activity it triggers in you is very rich and complex.
-- Rob Tannenbaum, "A Meeting of Sound Minds: John Cage and Brian Eno," Musician 83 (Sept. 1985)