The Color Kittens The Color Kittens The Color Kittens is a children's book by Margaret Wise Brown, illustrated by Alice and Martin Provensen published as part of the Little Golden Books series in 1949. The story revolves around two kittens, "Hush" and "Brush," who attempt to create green paint through mixing their other paints. Their attempts lead to a variety of different hues—none of them green. The book's famous catch phrase is "Blue is blue, and red is red! They still need green!" Children's book author and illustrator Paul O. Zelinsky, for whom the book was a childhood favorite and inspiration, said that,
Primary color The Natural Color System is also directly inspired by the psychological primaries. There are numerous competing primary colour systems throughout history. Scholars and scientists engaged in debate over which hues best describe the primary color sensations of the eye. Thomas Young proposed red, green, and violet as the three primary colors, while James Clerk Maxwell favoured changing violet to blue. Hermann von Helmholtz proposed "a slightly purplish red, a vegetation-green, slightly yellowish, and an ultramarine-blue" as a trio. In modern understanding, human cone cells do not correspond precisely to a specific set of primary colors, as each cone type responds