One of the better submissions so far:
If you visit a farm, you'll notice it stinks like manure. But if you live there, you don't notice a thing.
Unlike the frog metaphor, it is biologically true that the intensity of a smell drops after the nose adjusts, but this phrase doesn't have the same deadly message. Another reader:
There are good natural selection reasons why a simple biological analogy will be false. But not if you change the valence of the end state.
If I try to run 6 miles today, I'll probably give myself a heart attack. But if I jog a quarter mile today, and tomorrow, and every other day this week, and then a half mile every day next week, and three quarters mile the third week etc, then in 6 months, I'll be able to run 6 miles.
And there are analogies from perception. One is the volume on your car stereo which you turn up just a bit, and then up just a bit, and then up just a bit. Then you get home and turn the car off. When you get back in the car, "Boom!" How did the volume get to be so loud? So you dramatically reduce the volume on the stereo and on the way to work you turn the volume up just a bit, and then up just a bit…
(Photo: Andy Lyons/Getty.)
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