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Why it took us thousands of years to see the colour violet

psyche.co

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Re: Why it took us thousands of years to see the colour violet

#11

Post by thanatos519 »

jbay808 wrote: post #5
jagrsw wrote: post #4

So, what is violet actually? WIkipedia says both that it's blue near end of visible spectrum, and then adds that it's mix of blue and red with more blue than red. Those both seem contradictory. AFAIK human eye doesn't differentiate between wavelenghts of blue, it just compares intensity of whatever triggers its blue cones to whatever triggers its red/green cones, no? Or, maybe it's the fact that some ranges of ultrav…

As I understand it, the cone cells in your retina responsible for "red" have a second peak on the violet-side of blue. This means that a violet wavelength will get efficiently absorbed by both the "blue" and "red" receptors but not the "green" receptors. That sort of creates a "periodic boundary condition" to colour perception, wrapping a monotonic wavelength spectrum into a colour wheel.

This is also my understanding. The lowest visible frequency is close to half of the highest visible frequency so there might be some harmonics at work in this mechanism.

When I set my LED lights to RGB(0.1,0,1), it looks very much like my blacklights (UV LED, or 405nm lasers. and maybe I should get a tube to compare). I can tell them apart because the physical offset of the R and B LEDs makes a bit of visible fringing, or maybe it's that the single violet photons are coherent (with themselves) whereas the red and blue photons are not, or maybe the retina is a subtler instrument than its simple physical description suggests.

Re: Why it took us thousands of years to see the colour violet

#12

Post by cblconfederate »

> Egypt, Mesopotamia and the medieval Islamic cultures survived especially well in their extremely dry climates. And they had no violet in them at all.

In ancient times purple was a luxury for dying clothes, even in medieval times, and harvesting sea snails for the dye was lucrative business between egyptians, phoeniceans etc. so how come they claim we can't see it?

I dont think their claim is true. What's next? "Why it took us decades to see rounded corners"?

Re: Why it took us thousands of years to see the colour violet

#14

Post by bsder »

varjag wrote: post #10
egypturnash wrote: post #8

This is completely ignoring the fact that for a long time, purple/violet dyes were really rare and expensive. "Royal purple" was called that because only royalty could afford it . https://en.wikipedia.org/wiki/Tyrian_purple

This fact is completely addressed in the article, pointing out that aquamarine and other colors were expensive as well yet it never stopped the artists.

Tyrian purple was way more expensive than ultramarine. It required vast numbers of snails for very small amounts of dye. When royalty couldn't afford it, the production method was lost very quickly.

In addition, I'm pretty sure it didn't have a stable solid form. It also wasn't a particularly stable color (Tyrian purple robes would change color over time).

Both of those, by themselves, would be enough to preclude its use by artists. The cost was just adding insult to injury.

Re: Why it took us thousands of years to see the colour violet

#15

Post by bsder »

andreareina wrote: post #3

The speculation in this article is pretty bad; a shower of cosmic rays isn't going to affect everyone in the planet the same way to all of a sudden enhance their perception of violet. The much likelier explanation is that it's "just" a cultural development.

Exactly. It is not that unusual to find cultures and languages that do not distinguish between "green" and "blue", for example.

Re: Why it took us thousands of years to see the colour violet

#16

Post by irthomasthomas »

Not read the article yet but commenting while I remember... Prime Minister Gladstone who translated Homer in his spare time, thought that the ancient Greeks, or at least Homer where colour blind. Gladstone said "We have a great deal of difficulty in translating Homer’s colour terms into modern western languages" Homer, apparently had the colour literacy of a modern child, he described oxen as the colour of the sky and described the sea as wine-dark. Though many of Homers colours may just be poetic. Gladstone used to argue with Tennyson, who also translated Homer. They would take turns reading to each other and then debate the relative merits of each other's choices. It takes a poet to read a poet.

Re: Why it took us thousands of years to see the colour violet

#17

Post by fsloth »

irthomasthomas wrote: post #16

Not read the article yet but commenting while I remember... Prime Minister Gladstone who translated Homer in his spare time, thought that the ancient Greeks, or at least Homer where colour blind. Gladstone said "We have a great deal of difficulty in translating Homer’s colour terms into modern western languages" Homer, apparently had the colour literacy of a modern child, he described oxen as the colour of the sky an…

To my understanding the strange wording was caused by the requirements of the poetic construct the narration used. So they are filler to make other stuff fit. They are like punctuation. They are not trying to describe colors as such and should not be used as evidence how the people who spun the poem saw colors in psychological sense, I think.

Re: Why it took us thousands of years to see the colour violet

#19

Post by fsloth »

I do appreciate the feet-on-the ground research sentiment

"Over the past 20 years, I visited 193 museums in 42 different countries. Equipped with 1,500 Munsell colour chips .. I examined 139,892 works of art, searching for violet. ... there were only .. few artworks before the 1860s"

And the art historical conclusion feels convincing

"in 1864 the influential French art critic Charles Blanc ... described how violet, produced by mixing red and blue, is intensified by placing it next to yellow."

But unfortunately the last paragraph kind of places this immediately into pseudoscientific territory IMO. I wish humanists who do interesting research would not add nonsensical flourish like this:

" I can’t help but wonder whether a muon shower might have enhanced our ability to see violet midway through the 19th century on Earth."

Re: Why it took us thousands of years to see the colour violet

#20

Post by irthomasthomas »

fsloth wrote: post #17
irthomasthomas wrote: post #16

Not read the article yet but commenting while I remember... Prime Minister Gladstone who translated Homer in his spare time, thought that the ancient Greeks, or at least Homer where colour blind. Gladstone said "We have a great deal of difficulty in translating Homer’s colour terms into modern western languages" Homer, apparently had the colour literacy of a modern child, he described oxen as the colour of the sky an…

To my understanding the strange wording was caused by the requirements of the poetic construct the narration used. So they are filler to make other stuff fit. They are like punctuation. They are not trying to describe colors as such and should not be used as evidence how the people who spun the poem saw colors in psychological sense, I think.

Exactly so. I updated my comment to try and reflect that. Gladstone took it all too literally and would argue with Tennyson, who was better able to grasp the poetry in Homer.
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