The reason we see red, green, blue, and yellow as special is because they match the most extreme light patterns found in nature.
March 26, 2026
Original Paper
Emergence of unique hues from sparse coding of color in natural scenes
arXiv · 2603.24293
The Takeaway
Scientists have long wondered why certain hues feel 'pure' while others feel like mixes. This study used AI to show that our brains evolved to prioritize these specific colors because they represent the mathematical outliers of natural scenes, essentially tuning our subjective experience to the statistics of our environment.
From the abstract
Our subjective experience of color is typically described by abstract properties such as hue, saturation, and brightness that do not directly correspond to sensory signals arising from cones in the retina. Along the hue dimension, certain colors -- red, green, blue, and yellow -- appear unique in that they are not perceived as a combination of other colors, and the pairs red-green and blue-yellow appear opposites. However, the anatomical and physiological correlates of these 'unique hues' within