Abstract

For most of us, the phrase "all the colors of the rainbow" conjures an image of the natural rainbow¹ as a paragon of color variety and vividness. Indeed, both our language and art often invoke the rainbow as a color palette without peer.² Yet as a color standard, the rainbow has an oddly contentious history. For example, arguments about the number of rainbow colors date to antiquity, with observers as keen as Aristotle³ (who favored three colors) and Seneca the Younger⁴ (who favored an indefinite number) among the disputants. That this disagreement still persisted in Georgian England² (and indeed to the present) hints that the rainbow poses special perceptual problems.

© 1990 Optical Society of America