自相矛盾

集jí市shì上shàng，有yǒu一yī个人gè rén在zài卖mài矛máo和hé盾dùn。

In the market a man was selling spears and shields.

他tā举jǔ起qǐ盾dùn说shuō：我wǒ的de盾dùn最zuì坚固jiān gù，什么shén me矛máo都dōu刺cì不bù破pò它tā！

He held up a shield: 'My shields are the strongest, no spear can pierce them!'

他tā又yòu举jǔ起qǐ矛máo说shuō：我wǒ的de矛máo最zuì锋fēng利lì，什么shén me盾dùn都dōu能néng刺cì破pò！

Then he raised a spear: 'My spears are the sharpest, they pierce any shield!'

有人yǒu rén问wèn他tā：用yòng你nǐ的de矛máo，刺cì你nǐ的de盾dùn，会huì怎么样zěn me yàng呢ne？

Someone asked: 'And if I stab your shield with your spear, what then?'

他tā一句话yī jù huà也yě说shuō不bù出来chū lái。说话shuō huà做事zuò shì，前后qián hòu不bù能néng互相hù xiāng矛盾máo dùn。

He had no answer. What you say and do must not contradict itself.