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Existence is not its own justification.

The best ideas often come from those who work closest to the problem.

The world is a great sky, and we are the birds.

Psychology must be a purely descriptive science.

A proof is a device for convincing someone else that a mathematical statement is true.

"El amor es una fuerza que nos impulsa a seguir adelante, a pesar de todo."

我相信只要你付出努力，結果自然會來。