Chinese Idiom Stories for Software Professionals: #10 Self-Contradictory (自相矛盾)

Some people don’t believe what they say.

Zhimin Zhan
4 min readApr 1, 2022


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This article is one of the “Chinese Idiom Stories for Software Professionals” series.


Once upon a time in China, there was a man who sold spears as well as shields for a living.

One day, he held up a shield and said: “My shield is very strong. No matter how sharp a spear is, it cannot pierce my shield.”

After that, he held up his spear and bragged: “My spear is very sharp. No matter how strong a shield is, my spear can pierce it.”

One of the audience asked him: “What would happen if your spear is used to pierce your shield?”

The man was so embarrassed that he could not utter a single word.


This idiom is usually used to describe that some people are inconsistent in their words and deeds.

I really liked this simple and insightful idiom story when I heard it the first time (under 10 years old).

Examples in Software Development

In real life, ‘Self-Contradictory’ cases do happen a lot, it is less obvious than in this idiom story, however, the principle remains.

Test Automation in Agile

Nowadays, many IT companies/divisions claim that they are doing Agile. I once show this slide in my presentation at a software company (which claimed to do agile, and hired a handful of ‘agile coaches’).

Most attendants nodded their heads. Then, I showed this.

The meeting room was silent.

Too many meetings?

During this summer holiday, my daughter was working in a large firm as an intern. A few weeks ago, an email was sent to all the interns to ask them to watch Jason Fried’s TED talk: “Why work doesn’t happen at work”.



Zhimin Zhan

Test automation & CT coach, author, speaker and award-winning software developer. Help teams succeed with Agile/DevOps by implementing real Continuous Testing.