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Operational effectiveness and strategy are both essential to superior performance, but they work in very different ways.

The world is not a problem to be solved; it is a living being to which we belong.

Learning is not a matter of trial and error, but of insight.

Mathematics is not a deductive science—that's a cliché. When you try to prove a theorem, you don't just list the hypotheses and then start to reason. What you do is trial and error, experimentation, guesswork.