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Learning consists in the modification of certain mediating processes which operate between the stimulus and the response.

我不是悲觀主義者。我是一個受過現實主義訓練的樂觀主義者。

No individual has any right to come into the world and go out of it without leaving behind him distinct and legitimate reasons for having passed through it.

When we thin forests with purpose, we're not taking away life—we're making room for more life to flourish.

通往善的道路就是通往真理的道路。