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真正的幸福來自內心的滿足。

The truth is, the science of Nature has been already too long made only a work of the brain and the fancy: It is now high time that it should return to the plainness and soundness of observations on material and obvious things.

挫折不是懲罰，而是學習的機會。

閱讀是打開世界的鑰匙。