A novice was trying to fix a broken Lisp machine by turning the power
off and on.
Knight, seeing what the student was doing, spoke sternly: “You cannot
fix a machine by just power-cycling it with no understanding of what
is going wrong.”
Knight turned the machine off and on.
The machine worked.
http://www.catb.org/jargon/html/story-of-mel.html
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