在数学中，提出问题的艺术必须比解决问题更有价值。

The aim of every artist is to arrest motion, which is life, by artificial means and hold it fixed so that a hundred years later, when a stranger looks at it, it moves again since it is life.

出自先秦《荀子·非相》。赠人以有益之言，比赠人以金石珠玉更显珍贵。说明有益的建言对他人事业人生的助益作用。