“…In 1664, Sir Isaac Newton, followed by Hermann von Helmholtz in 1867, delineated component bands of colored light, or spectral chromatic bands, by drawing lines perpendicularly through spectra. Newton specified seven chromatic delineations in the spectrum (red, orange, yellow, green, blue, indigo, and violet; as referenced in Shapiro, 1984), whereas Helmholtz identified only four color sections (red, green, blue, and purple) in a prismatic spectrum (Campbell, 1986). 13 To our knowledge, there are no existing theories that provide behavioral predictions for Newton's task of delineating chromatic bands perceived in the spectrum.…”