the colour spectrum is not one dimensional because it is determined both by the frequency of light and by the response of each of the different cones in our eye

the colour spectrum is not one dimensional because it is determined both by the frequency of light and by the response of each of the different cones in our eyes to it. I have no opinion on the claims made by the article either way, I just wanted to point out that just because the frequency of light had a single dimension, it did not follow that there was a single colour axis.