Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Why Japan has blue traffic lights instead of green

rd.com

Post reply on HN
Print view View original

181–190 of 268 posts

Re: Why Japan has blue traffic lights instead of green

#181

Post by Cockbrand »

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

Like many siblings, I'm male and got a perfect score as well. I don't think that I have perfect vision, but I'd rather assume the test is flawed.

Re: Why Japan has blue traffic lights instead of green

#182

Post by bigstrat2003 »

bluGill wrote: post #88
the_mitsuhiko wrote: post #22

Earlier quoted context omitted.

> They speak of this as if it was a Japan-only thing. Which other countries have blue traffic lights?

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.

Re: Why Japan has blue traffic lights instead of green

#183

Post by hangonhn »

vinnyvichy wrote: post #73
yznlp wrote: post #29

Not a linguist. I feel like this is just an issue of imperfect correspondence between the word "blue" in English and "ao" in Japanese. The article explains the historical reason why ao encompasses both blue and green, so I think the concept of semantic field comes into play here. As an analogy, a MacBook is a type of laptop, and laptops, desktops and tablets are all IT devices (for lack of a better word). Apple might…

As an sort of counterbalancing aside, there are two common japanese words for red, the slightly less well known to foreigners is the name for the color of the sun on the japanese flag: beni/kurenai (a deeper red). Well Chinese has the parallel kanjis too but as far as I understand it for the Chinese the semantic values are flipped: https://www.quora.com/What-is-the-difference-between-%E8%B5%...

Chinese has yet another word for red: 彤. It closer to vermillion or what some people might recognize as "Chinese red" that one sees painted on doors and temples.

Re: Why Japan has blue traffic lights instead of green

#184

Post by monkeywork »

NoMoreNicksLeft wrote: post #125
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.)

It's juice of the fruit-called-orange. How is that not orange juice? We don't call apple juice "red juice" or grape juice "purple juice". If there's a language in the world where the color and the fruit aren't the same word, I've yet to learn it.

>grape juice "purple juice"

That I have seen

Re: Why Japan has blue traffic lights instead of green

#185

Post by yumraj »

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

What's the scale is not clear. It says 0 is perfect but what about 5?

While comparing it shows typical scores as -(large number) to +(large number).

Re: Why Japan has blue traffic lights instead of green

#186

Post by Arelius »

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

A lot of that is learned..

However, there are people who are tetrachromats, have cones most sensitive to a fourth frequency of light in their eyes, and those people are also overwhelmingly women.

Re: Why Japan has blue traffic lights instead of green

#187

Post by crazygringo »

NoMoreNicksLeft wrote: post #125
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.)

It's juice of the fruit-called-orange. How is that not orange juice? We don't call apple juice "red juice" or grape juice "purple juice". If there's a language in the world where the color and the fruit aren't the same word, I've yet to learn it.

No one's disputing that.

What's funny is that most people don't seem to realize that that the color of the juice isn't the color of the rind.

Just look at illustrations of orange juice on Google Images:

https://www.google.com/search?q=orange+juice+illustration&tb...

Most of them are showing an orange liquid that matches the color of the orange rind. It's hilarious. Because somehow, most people don't realize orange juice is yellow, even though they might drink it every morning.

Re: Why Japan has blue traffic lights instead of green

#188

Post by groos »

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…

How old are you roughly? The reason I ask is that the eye lens yellows with age and transmits less blue and violet through. So colors that would look blue-green to a younger eye would look more green to an older one.

Re: Why Japan has blue traffic lights instead of green

#189

Post by arjie »

It's a nice article and has lots of details.

But I searched my photo history for Japan and here are the first few that have traffic lights in them: https://imgur.com/a/S815y7o

This should help you determine what colour the lights are in your perception. Some are taken with a Canon DSLR and some are taken with a Pixel 3.

Re: Why Japan has blue traffic lights instead of green

#190

Post by Arelius »

kipchak wrote: post #176
chrisdsaldivar wrote: post #118

Earlier quoted context omitted.

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 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 sensitive to distinctions in blue-green.

Post reply on HN