Spear and shield
 
Here’s another Chinese idiom with an interesting story. The idiomatic English translation of 自相矛盾 (zì xiāng máo dùn) is “contradicting oneself”. The story behind it goes like this:
 
In ancient times, there was a sword and shield salesman who would yell out to people passing by, “My spears are the sharpest in the world and can pierce anything.” But with the very next breath, he would say, “My shields are the strongest in the world, and nothing can penetrate them!” One day, someone asked him, “What happens if someone throws one of your spears at one of your shields?”
 
That’s where the story ends, and it’s where today’s idiom and the Chinese word for contradiction (矛盾 - máo dùn), literally meaning spear shield, come from.