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Why Japan has blue traffic lights instead of green

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Re: Why Japan has blue traffic lights instead of green

#191

Post by rottencupcakes »

chrisdsaldivar wrote: post #118
doubled112 wrote: post #109

Earlier quoted context omitted.

I'm glad you mentioned that you had your wife confirm, because I'm convinced my wife sees more colours than I do, and I can't be the only one. I've had this exact discussion. What colour is this? Blue. No, can't you see it's green? Maybe it has some green in it Okay, so is it blue or green? Yes! Why did you ask me then?

Yes, on average women can perceive more colors than men [1] Anecdotally, in high school we all took this test for a class [2] and the girls did a lot better than us. Although some guys were able to score pretty well on it. I don’t remember if this was the exact test but it’s very similar. [1] https://pubmed.ncbi.nlm.nih.gov/21675035/ [2] https://www.xrite.com/hue-test

I scored a 6, but their lack of data on the distribution of scores makes that pretty hard to interpret.

Does anybody know how to read that?

Re: Why Japan has blue traffic lights instead of green

#192

Post by bluGill »

bigstrat2003 wrote: post #182
bluGill wrote: post #88

Earlier quoted context omitted.

The US. They are mostly green, but a lot of them have a blue tint for the colorblind. I suspect other countries as well, colorblindness is very common and this is a simple adaptation.

I wouldn't call "green with a slight blue tint" a blue light, personally. That's still a green light.

As someone who has trouble seeing green, often I would call them blue. I don't expect my experience is normal.

Re: Why Japan has blue traffic lights instead of green

#193

Post by bluGill »

marcosdumay wrote: post #158
bluGill wrote: post #85

Earlier quoted context omitted.

Most green lights in the US have a blue tint so that color blind people can see the blue. Most but not all, which is really frustrating as a colorblind person. More than once I've been sitting at a light until my wife told me it was green as there is one light near me without that blue tint. (we are making a left turn so light has both the round red stop light and the green left turn arrow on at the same time)

I'm pretty sure the international agreement on road signaling completely forbids any stop and go light from being on the same place, so that you can distinguish them without depending on any color. But well, the US never follows any agreement it signs, so yeah, that happens.

Sure, but green is so washed out for me that the green position may not be there at all for all the good it goes. If you tell me the green is lit I'll look close and see it is on, but I will not notice without being told to look.

Re: Why Japan has blue traffic lights instead of green

#194

Post by crazygringo »

dragonwriter wrote: post #153
crazygringo wrote: post #104

Earlier quoted context omitted.

And orange juice is actually yellow. Which really blows some people's minds. "Well it's a little bit orange." No it's not, not your regular American bottled or fresh OJ. Straight-up yellow. (Not denying there are varieties that produce more orange-color juice, like tangerines. But that's not what's on 99% of Americans' breakfast tables.)

> Which really blows some people's minds. "Well it's a little bit orange." No it's not, not your regular American bottled or fresh OJ. Straight-up yellow. Well, it wouldn't be that weird if you were right because we name fruit juices after the fruit, not the juice color, but I’ve never seen orange juice that wasn't distinctly on the orange side of yellow, even if its more yellow than orange, including fresh and bottl…

You're just proving my point, of how people insist it's still somehow orange.

Sure, almost nothing is perfectly a 60° hue of yellow. But the color orange is all the way at 30°.

And if you look at the HSL values of the juice in product photos like the following, you'll get hue values of around 52°:

https://www.amazon.com/Tropicana-Orange-Juice-No-Pulp/dp/B07...

https://www.amazon.com/Simply-Orange-Pulp-Juice-Drink/dp/B07...

That's just straight-up part of the band that we call yellow.

For comparison, here's the first result for "banana" in Google Images:

https://www.smithsonianmag.com/science-nature/building-a-bet...

It's 48°, even closer to orange than orange juice. Yet nobody goes around insisting that bananas are "on the orange side of yellow".

It's a case of linguistics somehow trumping what we literally see with our own eyes. It's actually quite astonishing how strong the effect is, even when it's pointed out to you.

Re: Why Japan has blue traffic lights instead of green

#195

Post by fenomas »

thaumasiotes wrote: post #154
fenomas wrote: post #108

Earlier quoted context omitted.

The word "ao" in Old Japanese already had the blue/green confusion before the character 青 was borrowed to write it, so if classical Chinese did as well I guess that would be two such languages.

> The word "ao" in Old Japanese already had the blue/green confusion before the character 青 was borrowed to write it What would the evidence for this be? It's clear that the word "ao" does not derive from the Chinese pronunciation of 青. But its meaning could easily have shifted under the influence of the spelling. Do we have a source that writes the word without spelling it 青?

This? https://ja.wikipedia.org/wiki/青#やまと言葉の「あお」

Re: Why Japan has blue traffic lights instead of green

#196

Post by jamseason »

lewispollard wrote: post #84
troad wrote: post #50

Earlier quoted context omitted.

I trained as a linguist and you hit the nail on the head. Word meanings are fuzzy clouds of references and nuances, and every language has slightly different clouds. There is nothing magical about this, despite the recurrent lizard-brain notion that words or names are somehow mystical and intrinsic, and that these differences must somehow be meaningful. Differences are quite common with colour terms - you don’t need…

> it doesn’t actually matter what convention they pick, so long as everyone agrees on it and sticks to it. That would be a good point, if that actually happened, but Japanese traffic lights have a mixture of green for go and blue for go (with most of them being green).

The Japanese specification for the color of traffic lights is certainly written in Japanese. If the specification says the light should have color "ao", then either blue or green or something in between that matches it is OK.

That the color region that word encompasses doesn't match that of the English words "green" doesn't really matter, and is not particularly mysterious.

Re: Why Japan has blue traffic lights instead of green

#197

Post by jrockway »

arp242 wrote: post #165
vages wrote: post #95

Earlier quoted context omitted.

I am looking out my hotel room window in Hiroshima in this very instant, and I even got my wife to confirm it: The traffic lights definitely are GREEN.

Please report the exact wavelength for verification.

Colors are not necessarily a single wavelength, and the human visual system can't distinguish between identical "tristimulus" caused by a single wavelength or a mixture of wavelengths. This is why color monitors with red, green, and blue pixels work. The red, green, and blue are designed to stimulate your long, medium, and short wavelength receptors. Models like CIE1931 map wavelengths to tristimulus values, which your monitor then maps to the right intensity of its red, green, and blue. (Display technology is, of course, imperfect. You can see redder reds, greener greens, and bluer blues than your monitor can emit, though newer monitors with Adobe RGB or DCI-P3 have redder reds. It's also possible that the green light from your monitor is not perfectly stimulating only your medium wavelength receptors.)

Some colors that look very real cannot be a single wavelength of light, like magenta. That color is a figment of our imaginations. (Rather, there is no wavelength of light that stimulates your long wave receptors and short wave receptors without stimulating the medium wave receptors. But, magenta does, because it's actually a blue wavelength and a red wavelength.)

Re: Why Japan has blue traffic lights instead of green

#198

Post by NovemberWhiskey »

2143 wrote: post #86

Just a data point that I want to put out there. I have long heard that Japan has blue traffic lights. Earlier this year I visited Japan. Because I had heard about the blue traffic light situation, I paid special attention to the traffic lights. They all appeared green to me. In both Tokyo and Osaka. Okay maybe a tinge of blue if you look at it and wonder 'is this blue?' , but the only reason I wondered was because I…

The "go" signal in traffic lights in Japan is 青い (あおい) "aoi".

That adjective in Japanese means both blue and green. The Japanese language didn't have a widely-adopted word for just "green" - 緑 (みどり) "midori" - until after WWII.

Green apples or vegetables are still "aoi", for example. I lived in Japan for four years and never saw a blue traffic light.

Re: Why Japan has blue traffic lights instead of green

#199

Post by kalensh »

Arelius wrote: post #190
kipchak wrote: post #176

Earlier quoted context omitted.

I wonder if there might be a language aspect to this, with males in the US generally having less familiarity with words for the in between colors leading to more difficulty distinguishing between them, with people with more words for greenish shades for example having an easier time seeing different shades of green. https://boingboing.net/2011/08/12/how-language-affects-color...

I'd have to dig up references, but I understand it's a pretty well documented effect that having words for colors is directly related to a population seeing more distinction for those colors. If I recall, some early societies didn't have a distinction between green and blue. Given that blue often doesnt show up naturally outside of the sky and it's reflections. And in those populations they would be much less sensiti…

Which is exactly what the article is about ;) (Well, one example of an early society that didn't distinguish between green a blue.)

Re: Why Japan has blue traffic lights instead of green

#200

Post by erutuon »

thaumasiotes wrote: post #46

> Hundreds of years ago, the Japanese language included words for only four basic colors: black, white, red, and blue. If you wanted to describe something green, you’d use the word for blue—“ao”—and that system worked well enough until roughly the end of the first millennium, when the word “midori” (originally meaning “sprout”) began showing up in writing to describe what we know as green. There's something going on…

As far as I can tell from Wiktionary (https://en.wiktionary.org/wiki/%E7%B7%91#Japanese), though I don't speak Japanese, the Japanese word midori has had the meaning "bud" or "sprout", but the Chinese words written with the same character don't. Spelling and word identity are distinct. This confuses me sometimes when looking up Japanese words.
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