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A person with normal colour vision can tell apart somewhere between one and ten million shades, depending on how they are counted. Yet most languages manage with a dozen or fewer basic colour words, such as red, blue or green.

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Colour vision begins with three kinds of cone cells in the retina, the light-sensitive layer at the back of the eye. Each kind responds best to short, medium or long wavelengths of light, roughly blue, green and red, and the brain compares their signals to produce every shade we see. Counting those shades is hard, which is why estimates vary so widely. In 1969 the anthropologist Brent Berlin and the linguist Paul Kay compared languages and found that they have between two and about a dozen basic colour terms; English has eleven. Languages also divide the spectrum differently. Russian has separate basic words for dark blue, siniy, and light blue, goluboy. A 2007 study reported that Russian speakers told two blues apart faster when one was siniy and the other goluboy, an advantage English speakers did not show, but researchers who repeated the experiment in 2020 did not find it.

Türkçe oku
Renkleri normal gören bir insan, nasıl sayıldığına göre bir ile on milyon arasında renk tonunu birbirinden ayırt edebilir. Oysa dillerin çoğu kırmızı, mavi, yeşil gibi en fazla bir düzine temel renk adıyla yetinir.

Renkli görme, gözün arkasındaki ışığa duyarlı tabaka olan retinadaki üç tür koni hücresiyle başlar. Her tür en çok kısa, orta ya da uzun dalga boylu ışığa, kabaca maviye, yeşile ve kırmızıya tepki verir; beyin bu üç sinyali karşılaştırarak gördüğümüz bütün tonları üretir. Bu tonları saymak zor olduğu için tahminler bu kadar farklıdır. Antropolog Brent Berlin ile dilbilimci Paul Kay 1969'da dilleri karşılaştırdı ve temel renk sözcüklerinin sayısının ikiyle bir düzine arasında değiştiğini gördü; İngilizcede on bir tane vardır. Diller renk yelpazesini farklı yerlerden de böler: Rusçada koyu mavi (siniy) ile açık mavi (goluboy) için ayrı temel sözcükler vardır. 2007'deki bir çalışmaya göre Rusça konuşanlar, biri siniy öbürü goluboy olan iki maviyi daha hızlı ayırt ediyordu; İngilizce konuşanlarda böyle bir fark görülmedi. Ancak deneyi 2020'de tekrarlayan araştırmacılar bu hız farkını bulamadı.

Sources and further reading

Background reading: Color vision
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