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Traffic lights: are the Japanese color blind?

Throughout the world we know the colors of traffic lights with the three colors: Green, Orange and Red... except in Japan where they are Blue, Yellow and Red. For what ?

Rooted in the regulation of rail traffic, traffic lights for road vehicles first appeared in the United States in 1912 in Salt Lake City. It's an invention of Lester Wire, the city's police officer. It is yellow and made with red and green lenses inspired by colors used in the navy and railways. The American Traffic Signal Company then adopted his idea and began installing it in the country from 1914, first in Cleveland, then in New York and Detroit. At the time, the signals were only two colors (red and green) and were controlled manually by a police officer installed in a cabin. In addition, a bell was heard during changes to warn motorists.

In 1920, the first electric traffic lights were installed and a few years later, in 1923, they began to appear on European soil. The installation of traffic lights was of course intended to facilitate the regulation of vehicle traffic on the roads and to improve safety levels, since the number of vehicles in circulation had increased to such an extent that the use of traffic lights was imperative.

The colors used at traffic lights in Greece are determined by the Vienna International Convention on Road Traffic of 1968, which has been signed by a total of 71 states. The purpose of this Convention was to adopt an international treaty intended to facilitate international road traffic and increase road safety by establishing uniform traffic rules between the contracting parties.

Japan is not among the signatories. In Japan, road signs (道路標識, dōro-hyōshiki?) are officially standardized in the “Decree on Road Signs and Markings” (道路標識、 区画線及び道路標示に関する命令) published in 1968. It is largely inspired by the “Decree on the Standardization of Road Signs” issued by the Tokyo Metropolitan Police Department in 1938 and the “Decree on Road Signs” of the Ministry of the Interior published in 1942.

Brief! a little historical tour to be able to answer the question of the Day: Are the Japanese color blind for having used traffic lights: Blue, Yellow and Red?

The reason why Japan uses both blue or green-blue instead of green in its traffic lights comes from the Japanese translation of the treaty of the Vienna International Convention on Road Traffic of 1968. In translation of this treaty which defined the standards of the Vienna Convention, was the absence of a separate word in the Japanese language for the colors blue and green, the Japanese using the same word (ao) for blue and green!

Ao, one of the oldest words for a color in Japanese, once covered broad shades. Thus, it can be used to describe the bright green of the new vegetation at the start of summer. In the same way, let us cite the terms aoba (new leaves), aona (green leafy vegetables), aomame (green peas or soybeans), or even the prefecture of Aomori, whose name apparently comes from a forest (mori) of pine trees which covered the small hill where the headquarters of the prefecture is now located. Historically, Ao would also have been used to refer to an even wider palette of shades, including black, white or gray.

These changing meanings of the same word in the distant past can be as fascinating as they are confusing. According to the oldest records of Japanese language, the words ao and aka (red) were associated with the idea of clarity. While kuro (black) meant darkness and shiro (white) meant light, ao and aka were in between, ao for a darker shade, and aka for a lighter shade. Kuro and kurai (dark) share the same etymological root; aka is linked to the word akarui, which means “clear”.

The meaning of these terms has evolved over time, but the word ao has remained to designate the green color of Japan's traffic lights. The very first traffic light, imported from the United States, was installed in the Hibiya district of Tokyo in 1930. Originally, the legislation decided to designate the green light with the term midori, but public opinion insisted on changing it to ao. It has been this way ever since. In 1947, the term "green light" was included in Japanese law under the official name of ao shingô.

However, the Land of the Rising Sun's efforts to come closer to international standards have begun to change the color of traffic lights, adding more and more greenery.

After disagreements among linguists in 1973 over the wrong word used in official state documents, the Japanese government resolved the problem in the most unorthodox way. Instead of changing the word "ao" to the word "midori", in order to put an end to this problem once and for all, through a relevant decree, he decided to use a green color on traffic lights containing as much blue as possible.

For the orange light, it can be yellow or orange it depends on the country it seems to me, in Japan it is called "yellow light" (黄色信号) but hey it also tends a little towards orange.

So although traffic lights in Japan appear blue and yellow in many cases, they are actually green and orange, and have exactly the same meaning as the green traffic light everywhere else in the world.

Another particularity of traffic lights in Japan is that they are placed horizontally instead of traditionally vertical.

Traffic signs are not to be outdone, proud of their culture, the Japanese do not hesitate to make some fantasies in their signs.

In conclusion :

No, the Japanese are not color blind, but they just have a very colorful language.


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