I assembled the image below in google drive using screen captures from this lecture demonstration: https://www.youtube.com/watch?v=K7rwYjdRFRA.
Goethe's and Newton's spectrum https://drive.google.com/file/d/1SOIw83ljBDMOR9Kd8J0CyP5kBmZ7eQBS/view?usp=sharing The top row is a beam of white light reflected from a screen after it has passed through different size apertures. The bottom row is the spectrum that results when a prism is placed in front of the aperture. In contrast to Newton, Goethe maintained that white light is not made of coloured light, but rather coloured light arises at the boundary of white and dark. Goethe would say the blues and cyans arise from the white pushing into the dark and the reds and yellows arise from the dark pushing into the white. Goethe's view is supported by the images on the left. Of course, as the beam of light shrinks, the images on the right lend credence to Newton's idea that white light is made of coloured light. The video is in German but youtube can provide a crude text translation of the speech. The presenter Dr. Johannes Grebe Ellis says of Newton that when he revealed the nature of white light he also concealed something about it at the same time. Harry
