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"The line between good and evil is permeable and anyone can cross it when pushed by circumstances."

"The task of the modern educator is not to cut down jungles, but to irrigate deserts."

To forget is to be free.

The most important thing in science is not so much to obtain new facts as to discover new ways of thinking about them.

數學的語言是普遍的，超越了文化和語言的障礙。