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The truth is rarely pure and never simple.
真相很少是纯粹的,也从不简单。
数学不是关于数字、方程、计算或算法的:它是关于理解的。
"History is that certainty produced at the point where the imperfections of memory meet the inadequacies of documentation."
Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding.