Qin Shihuangdi first ruled China in 221 BC. He was the first Emperor, and laid the foundations for the world’s oldest continuous political entity. However, the preceding two hundred years could not have been more different. Named the ‘Warring States Period’, it was characterized by a disunited collection of fractious power-bases, border raids, mass wars, and political turmoil. From this period we get the apocryphal story of ‘sān rén chéng hǔx’, or ‘three men make a tiger’.

Out of sight, out of mind

During Qin Shihuangdi’s rule lived a man named Pang Cong. He was an official of the central state of Wei. As was (reasonably) common practice in those days he was, along with the king of Wei’s son, part of a hostage swap-deal. The hostage swap was with the newly befriended neighbouring state of Zhao.


Pang Cong – a talented minister – was worried about a whispering campaign against him while he was away.

The voice of a ‘gang’ is strong

Pang Cong illustrated the problem to the king of Wei with a hypothetical situation: If one person says a tiger is roaming the streets of the capital, would the king believe him? No, said the king. Pang asks him, if he hears the same from two people, would he believe them? Again, no, said the king. Pang asks him, if three people say there is a tiger roaming the streets of the capital, would he believe them? The king says yes – with three people saying the same thing he would believe it. And with that, Pang reminded him that a tiger roaming the streets of the capital is absurd, but equally as absurd is that if enough people say it is so, it becomes true even without any evidence.


The voice of a ‘gang’ is strong: Pang knew this.


He told the king that although he was a talented and faithful minister, he had more than three enemies in court and, if ‘three men make a tiger’, could three men make him a bad minister? The king of Wei understood what Pang Cong meant, and sent him off on the hostage swap-deal, promising to remember his abilities whatever he heard about him in the royal court.


I think we can say that Pang Cong was a clever minister, if only because he understood and illustrated the power of the influence that evidence of prevalence had – the gang – to his king more than 2,000 years ago.

Behaviour commonly performed

Evidence of behaviour commonly performed – or the descriptive norm – states that we adjust our actions and opinions according to the evidence of others’ actions – either directly observed (e.g. three men claiming a tiger roams the city, or in more modern times observing people queuing/waiting in line) or observing the artefacts of previous actions (e.g. a space empty of people but full of litter). There’s nothing wrong with that. In fact, there’s a lot right with it, as it’s a pretty good strategy for staying alive: if ‘they’re’ not eating it, I won’t eat it; If ‘they’re’ not going there, I won’t go there; etc. It allows us to navigate the world efficiently by removing the need to employ costly cognitive load to work out what to do every time we’re presented with a new choice.


In essence, we ‘borrow’ conclusions already established by others.

Thousands of reasons to shine a light

If a ‘behaviour commonly performed’ is a desirable behaviour or thought that one wishes to evoke or increase in others, it is often much more powerful to tell people how many other people conform (e.g. ‘there are many sightings of a tiger in the capital’), rather than to ask for an opinion to be adopted (e.g. ‘you must believe me that there is a tiger in the capital’).


You really do very little work other than shine a light on an existing circumstance.


And, as evidence of ‘behaviour commonly performed’ as a driver of actions was pervasive and widespread in China over 2,000 years ago, so it will be 2,000 years from now. We have plenty of time to get familiar with, and begin using, the descriptive norm.


Just don’t try to convince the king of Wei that Pang Cong was anything other than a clever minister. Or, if you do, use three or more of the king’s court to repeat your assertion; As Peng Cong knew all too well, ‘sān rén chéng hǔx’.

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