穷则变，变则通，通则久

事物发展达到极限或遇到困境时，需要通过变革才能找到新的通道，进而才能路路通达、持续发展。出自《周易·系辞下》，是对事物变化规律的一种认识。《系辞》认为，事物处于不断的变化之中，并且会在至极之时朝向对立面转化。人应把握这一事物变化规律，在穷极之时寻找变化的契机，促成事物的改变，以实现通顺而长久的发展。

Extreme-Change-Continuity

When things reach their extreme, change occurs. After the change they evolve smoothly, and thus they continue for a long time. This notion comes from The Book of Changes and is a way of understanding the principles of change. According to this text, things are constantly changing and will, when they reach their extreme, develop in the opposite direction. People ought to understand the way of change, look for the turning point when things reach their extreme, and facilitate change so as to effect their smooth and long-lasting development.

引例

《易》穷则变，变则通，通则久，是以“自天祐之，吉无不利”。（《周易·系辞下》）（《易》揭示，事物发展达到极限或遇到困境时，需要通过变革才能找到新的通道，进而才能路路通达、持续发展，所以能够“从上天降下佑助，吉祥而无所不利”。）

The Book of Changes reveals that when things reach their extreme, change occurs. After the change they evolve smoothly, and thus they continue for a long time. That's how "Heaven bestows help to the human world and benefits all". (The Book of Changes)