Charles F. Kettering, former research head of General Motors, was fond of telling this story. When he called a research and development meeting on a particular problem of not an immediate probability of presenting a ready solution, and he wanted the problem solved, he’d take care to first find a piece of cardboard and write in big, bold letters: No Slide Rulers Permitted. He’d then place the sign on a table outside the meeting room where it could be easily seen and read by each member of his design and development staff. When asked why he found it necessary to do this, he gave this reason: “The reason that the sign had become necessary is if I didn’t do that, I’d find someone reaching for his slide ruler. Then he’d be on
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