Take a look at the shop signs in front of you. Can you tell what kinds of businesses they belonged to?

These signs were used in Beijing around 1940 and were known as huangzi.

What makes them remarkable is that many contain very little writing. A cotton shop simply displayed cotton. A shoe shop hung up a shoe. Some signs are so symbolic that, without knowing the culture, their meaning is almost impossible to recognize.

One example is the sign for a restaurant serving Muslim customers. Its vivid blue color immediately stands out. In Islamic culture, blue has long been regarded as a sacred color, so people in Beijing at the time could recognize the restaurant at a glance.

Some shopkeepers also displayed a sense of wit. One tavern featured a line from a poem relating to the famous Chinese poet Li Bai:

"Though summoned by the Son of Heaven, I will not board the boat."

The verse describes a man so happily drunk that he ignores even the emperor's command. Li Bai was celebrated both for his poetry and his love of wine, making the quotation a perfect—and rather stylish—advertisement for a tavern.

These signs conveyed far more than practical information. They reflected the culture and character of the streets where they hung.

Collecting them was not easy. Museum collectors would ask shop owners if they would sell the signs outside their stores, only to be met with indignation.

"We're not so poor that we'd sell our own sign!" many replied.

Eventually, an antiques dealer devised a solution. He gave each owner enough money to commission a replacement sign, and in exchange, the old one was preserved.

Weathered by rain, faded by the sun, darkened by soot, and worn smooth through years of use, these were exactly the kinds of objects Shozen Nakayama believed deserved to be saved.

As Beijing modernized, huangzi gradually disappeared from its streets. Today, they are rarely seen, even in their place of origin. It is possible that this museum now holds one of the world's most complete surviving collections.

Yet what remains here is more than a collection of historic shop signs. Each one preserves the life of the person who ran the business.

May customers come today. May business be good. May I provide for my family.

Every morning, those hopes may well have rested in the very hands of the shopkeeper who had hung it. These signs were not only tools of trade, they were quiet expressions of hope, small everyday prayers for the life their owners wished to build.