Why was red selected for stop and green for go?

[M'Sharak]

http://en.wikipedia.org/wiki/Tipperary_Hill

I hope all the color-blind people there are well versed in local history.

You may have overlooked this, upthread.

Sure sucks if you're red/green colorblind, in any case.

According to the website I linked, the red light also contains some orange and the green light contains some blue to alert colorblind drivers.

(emphasis mine)

 

[RJDiogenes]

These colors have a psychological effect on people. Red, because it is the color of fire (or possibly blood, as noted above) triggers a sense of altertness. Green, being the color of trees or grass, is more benign (which is why it is also used now for hospital scrubs and so on-- to calm patients). Basically, these colors are used because they are consistent with the desired responses.

So... on Vulcan it's the opposite?

Vulcans stop when it is logical to do so.

 

[Redfern]

Wasn't there a movement during the rule of Chairman Mao in China to disassociate itself from "decadent western ways" going so far as to reverse the meaning of traffic lights, ergo, red = go and green = stop? Or was that propoganda "we" started to mock the Chinese?

Sincerely,

Bill

 

[Ln X]

I dunno know. It's one of those things in life, like there are 90 degrees to a right angle. You would think in the metric system it would be 25 degrees if one full rotation counted as a 100 degrees. But it's not, and in our heads 90 degrees is the angle that represents a right angle.

If it can't be explained than perhaps it's the grammatical equivalent of a mathematical axiom? One of those fundamental truths that can't be proven?

 

[Ar-Pharazon]

Wasn't there a movement during the rule of Chairman Mao in China to disassociate itself from "decadent western ways" going so far as to reverse the meaning of traffic lights, ergo, red = go and green = stop? Or was that propoganda "we" started to mock the Chinese?

Sincerely,

Bill

Considering all those youtube videos where dozens of Chinese are blowing through intersections, you may be onto something.

They might not know what color means what anymore.

 

[Holdfast]

I dunno know. It's one of those things in life, like there are 90 degrees to a right angle. You would think in the metric system it would be 25 degrees if one full rotation counted as a 100 degrees. But it's not, and in our heads 90 degrees is the angle that represents a right angle.

You think that's bad; the SI unit for angles is actually radians. A right angle in SI is pi/2 radians.

(it actually makes more sense to use radians than your suggested 100 degrees for a revolution, for mathematical/physics reasons, but on an everyday basis it's just as wacky as choosing degrees, minutes and seconds for angles )

Sure sucks if you're red/green colorblind, in any case.

I remember watching an episode of QI where they pointed out that the green used in traffic lights is actually very slightly blue. That would help some colour-blind people. Not all (colour-blindness has variation within its population), but quite a few.

As to why red is stop and green is go, I buy the idea upthread that railway usage preceded road usage, and that since red was associated with blood/danger it was a good choice for stop. That, and nature is predominantly green & blue (grass/trees & sky/water), so a red light would naturally stand out against it.

 

[{ Emilia }]

Sure sucks if you're red/green colorblind, in any case.

According to the website I linked, the red light also contains some orange and the green light contains some blue to alert colorblind drivers.

Sure sucks if you're red/green colorblind, in any case.

I remember watching an episode of QI where they pointed out that the green used in traffic lights is actually very slightly blue.

Sometimes I have these Groundhog Day moments on trekbbs.

 

[Holdfast]

I never promised to read threads carefully.

 

[{ Emilia }]

I never promised to read threads carefully.

Well, it's only 2 pages!

 

[Holdfast]

I never promised to read threads carefully.

Well, it's only 2 pages!

That doesn't really improve the odds much... I generally start skim-reading after about the first reply...

 

[iguana_tonante]

I dunno know. It's one of those things in life, like there are 90 degrees to a right angle. You would think in the metric system it would be 25 degrees if one full rotation counted as a 100 degrees. But it's not, and in our heads 90 degrees is the angle that represents a right angle.

If it can't be explained than perhaps it's the grammatical equivalent of a mathematical axiom? One of those fundamental truths that can't be proven?

wut?

The equivalence 1 full rotation = 360 degrees is just one of many conventions. You can thank the Babylonians for that. The reason for that is most probably astronomical: History of the degree of arc.

The fact that you think right angle = 90 degrees in a right angle is habit, nothing more. No reason to invoke mathematical axioms and fundamental truths.