教，然后知不足

Another favorite Wheelerism is "one can only learn by teaching." Wheeler has been the supervisor for some 50 PhDs in physics during his career, an "enormous number," according to Jeremy Bernstein, a physicist and science writer. Wheeler's most famous student was the late Richard P. Feynman, who received a Nobel Prize in 1965 for his work in quantum electrodynamics.
诺贝尔奖得主诺曼的老师惠勒（Wheeler）曾经说过：“人只有通过教学才能真正学会。”
此言不虚，很多时候，能够自己明白是非常初级的感受，只有能将自己明白的事理明明白白讲出来让不明白的人明白才是真正弄懂了。
做父母的也是如此，只有身为人父、人母才能真正成为大人，当然不是所有的人都能成为合格的家长的。严格要求孩子做到的，自己必须做到。每每开车时，看到别人不守规矩，忍不住骂几句脏话的时候，后座的小朋友总会说：“爸爸，别说这样的话，不好听！”