During the Northern Song Dynasty, there was a prefect named Tian Deng who was autocratic and unreasonable. Because his name contained the character 'Deng,' he forbade anyone in his prefecture from using any character that sounded the same as 'Deng' in conversation. Consequently, any character that sounded like 'Deng' had to be replaced with another. Anyone who violated this taboo would be charged with insulting a local official, facing severe sentences or lighter corporal punishment. Many clerks and officers were flogged for uttering words that sounded like 'Deng.'

The annual Lantern Festival was approaching. According to custom, fireworks would be set off and lanterns lit for three days in the prefecture capital to celebrate. The prefectural yamen needed to post a notice in advance, inviting the common people to come and view the lanterns. However, the official responsible for writing the notice found himself in a difficult position this time. How should he write it? Using the character 'Deng' would offend the prefect; not using it would make the meaning unclear.

After much deliberation, the junior official decided to replace 'Deng' with 'Huo' (fire). Thus, the notice read: 'This prefecture will set fires for three days as per usual practice.'

When the notice was posted, the common people were alarmed and agitated. Especially some visitors from other regions were utterly bewildered, truly believing the government intended to set fires in the city for three days! They hastily packed their belongings, scrambling to leave this troubled place. The local residents, who were already extremely displeased with Tian Deng's autocratic and unreasonable behavior, were even more outraged upon seeing this notice from the yamen. They angrily exclaimed, 'Only officials are allowed to set fires, but the common people are forbidden to light lamps! What kind of world is this!'