Talk:Rainbow

5, 6 or 7 colours - how can I improve this article?

Before Newton, others proposed 5 or 6 colours. In fact Newton himself perceived five colours and only expanded the amount so as to fit into the contemporary meme of 7 as representing Biblical wholeness: the 7 days of the week, 7 notes of the musical scale, 7 planets (at the time Newton was alive), 7 Archangels etc. In the modern era there are several systems (RYB, RGB, CYMK; primary, secondary, tertiary etc) yet as colour perception is a highly individualised phenomenon (no two eyes are alike or see the same) the definition of colour is an abstract concept even though wavelength can be measured and isolated. One rare woman was reported to be capable of repeatedly identifying thousands of colours accurately, possibly in the millions. Perhaps Newton saw indigo jump out at him; many have trouble discerning the colour and identifying it in a line-up. Indeed the six-colour Rainbow Flag adopted by the LBGTQ+ community (minus indigo) is the simplest most practical depiction that even a child can comprehend easily.

I don't know how to do it but I would like to improve this article to reflect that the Newton-defined idea of the seven-coloured rainbow is not a universally accepted scientific concept. It is a teaching model yes, but otherwise, colours are abstract and arbitrary (in the eye of the beholder). Wokepedian (talk) 10:50, 3 May 2023 (UTC)

Start with finding a reliable source that discusses how others define the spectrum differently from Newton. There is already a section in the article that touches on this in regards to linguistic relativity. --Escape Orbit ^(Talk) 11:46, 3 May 2023 (UTC)

If I could chip in...Ogden Rood, an American physicist, used 10 or 12 colour divisions in "Modern Chromatics, with Applications to Art and Industry", 1879.

https://archive.org/details/modernchromatics00rood

He was pretty methodical, using colour wheels (like Maxwell) to achieve mixtures, and had some influence on Post Impressionist painters. Like Bezold in his "Farbenlehre" of 1874, Rood explicitly rejected 'indigo' in favour of ultramarine. (Many others in the 18th and 19th centuries had developed colour systems based on three painters' primaries of red, yellow and blue, and their mixtures, hoping to cover the whole visible range. Often, they were based on known pigments rather than spectral studies.)

On the subject of Biblical memes, there is little of that in Newton's 1704 "Opticks" (except for some alchemical mysticism in Queries at the end, mostly added in later editions). His musical framework, adding orange and indigo in the semitone intervals, was a clever device. Remember, the theory of music with its mathematical ratios was part of higher education at the time, and many books on the subject were circulating in England and abroad. Better than a dry set of calculations, "Opticks" was readily understood. No wonder it was popular.

Other than the musical matrix, there was no real way to quantify light. (Newton did make some attempts, guessing at sizes for colour particles.) In 1801, Thomas Young converted Newton's figures to wavelengths and frequencies. He gave colour its first tangible dimensions, but retained Newton's seven-fold division of ROYGBIV. (At the same time, Young proposed the red, green and violet-blue triad, as the basis for colour perception at the retina.) Thus the seven colours have endured; any selection of spectral colours – except for the convenience of naming them – would be just as arbitrary.

While I'm at it, here's a couple of my own links that might be useful here if you haven't already seen them. The first is to an essay on the history of the rainbow in art, including a discussion of 'indigo'. The second link is to pages on Newton's use of music in "Opticks".

http://www.colourmusic.x10host.com/rain.htm

http://www.colourmusic.x10host.com/opticks1.htm Nielshutch (talk) 19:08, 19 October 2023 (UTC)

Link update (Dutch)

I am trying to update a link on the Dutch version of this page –

https://nl.m.wikipedia.org/wiki/Regenboog_(optica)

It has in a module for References, near the bottom of the page. I can't crack it open (like the English references) nor understand the Dutch instructions. The specific reference reads –

"24. Bartholomaeus Anglicus, A lesson in the rainbow, in 14de-eeuws manuscript De proprietatibus rerum, colourmusic.info".

The 'colourmusic.info' tag at the end is not live, but refers to a web site that is due to expire in a couple of weeks. The updated link, now active, is –

http://www.colourmusic.x10host.com/rain.htm

The image referred to in the Reference is half-way down that page, and can also be accessed as –

http://www.colourmusic.x10host.com/class.gif

I have left this note on the Dutch Talk page, too (in English), but maybe someone here can tell me how to edit the References box on the Dutch page. Then I could make the change myself.

Otherwise, anyone else want to do the honours? Nielshutch (talk) 15:39, 28 October 2023 (UTC)

Done, I updated the link. Ceinturion (talk) 11:12, 29 October 2023 (UTC)

You're my hero, Ceinturion! Nielshutch (talk) 18:34, 29 October 2023 (UTC)

I am not sure if this is relevant or already on the page.

I couldn't find anything in this page about the original 3 colour rainbow in historical paintings. Sorry if I just accidentally missed it on page. If it's relevant and has proof, please include it in. If it's incorrect or I am misunderstanding something, please reply to me about this.YouTube short/Tiktok Aristotle also wrote, “There are never more than two rainbows at one time. Each of them is three-colored.” His three-colored assignation was accepted by scholars, scientists, and the public for many years. " Aristotle also wrote, “There are never more than two rainbows at one time. Each of them is three-colored.” His three-colored assignation was accepted by scholars, scientists, and the public for many years. " 2409:40E3:4035:4A2E:7CD2:58FF:FE1B:F5AC (talk) 06:12, 27 February 2024 (UTC)

Noah as first literary example?

The article says that the Noah flood story is the first example in literature, when it clearly is not. The flood story in the Epic of Gilgamesh, and the story of Utnipishtum is over 1000 years earlier than the first temple period. The Noah story is derived from the Gilgamesh story, right down to the rainbow being a promise to never drown humanity again. Maybe we're using the word "literary" too narrowly. I welcome being proved wrong, but I would like to know exactly how the claim is correct as it exists on the page. Neorunner (talk) 20:50, 12 June 2024 (UTC)