Children totally accept — and crave — family rules. “In our family we have a rule for X” is the only excuse a parent needs for setting a family policy. In fact, “I have a rule for X” is the only excuse you need for your own personal policies.
数学不仅仅是关于数字、方程、计算或算法:它是关于理解的。
不要归罪于天地陰陽的变化,一切都应责怪人事;不要对圣人抱有过高的奢望,一切都应求诸自身。
好的设计就是尽可能少的设计。