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"Picture books are the first art gallery many children ever visit."

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.

Money is concerned only with what is common to all, i.e., the exchange value, and it reduces all quality and individuality to the question: How much?

Mental phenomena are nature's experiments in survival.

樹(shù)葉的低語(yǔ)比董事會(huì)的辯論更有智慧。