The Parable of the Knobs
On generality and simplicity
“But you can’t have a general theory in sociology” the student assured me. “Things work differently in different places.”
So I told this story.
Jack stayed at a motel for a few days. It was a nice enough, but Jack always had trouble adjusting to a new environment. A particular source of confusion at this one was how to work the shower.
There were two knobs: one on the right side of the faucet was labelled “cold,” the one on the left was labeled “hot.”
They appeared to work according to completely opposite principles! To increase the amount of cold water, you needed to turn the cold knob to the right. But to increase the amount of hot water, you needed to turn the hot knob to the left.
Jack was a simple man. It was hard to keep track of which one increased by going to the right and which increased by going to the left. By his fourth day in the room, he had accidentally scalded or chilled himself several times. Why oh why couldn’t they both work the same?
Then he had a revelation: Both knobs actually did obey the same principle. Instead of remembering which one turned to the left and which one turned to the right, all he had to remember was “Turn away from the center.”
It was a funny, he thought, how they seemed different, even opposite, at first, but then later they seemed to be doing the same thing. He wondered how many other things were like that.
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