Global optimization over local perfection

## Three principles of system design 1. The trap of local optimization -- If you optimize the components, you will probably ruin the system performance. 2. Design for the Unknown -- Part of systems engineering design is to prepare for changes so they can be gracefully made and still not degrade the other parts. 3. The Danger of "Overfitting" -- The closer you meet specifications, the worse the performance will be when overloaded. --- Do global not local optimization 一个系统的整体韧性（Global Optimization）必须建立在其组成部分的“刻意不完美”之上。极度追求局部优化（Local Optimization），会抽干系统应对未知变化所需的冗余（Redundancy），从而剥夺系统在超载时“优雅降级（Graceful Degradation）”的能力。**要想赢得全局，就必须容忍局部的次优。** 真正的强大，不是在顺境中跑得最快（那是局部优化），而是在遇到未知和极端压力时，能够退得最从容、弯而不折。 > 拥抱粗糙的现实，不要过度拟合当前环境，保留冗余以应对时代剧变。 local overfitting 的后果 -- [[Structural dependence & institutionalization]] [[Schools create institutional dependency and leave them unprepared for real-world life and work]] (overfitting for the curriculum and ignoring the outside world)