The Bezold Effect

The Bezold Effect was named after Wilhelm von Bezold (1837–1907) who discovered it when experimenting with ways to modify rug design by only changing one color.

He recognized this effect when searching for a method through which he could change the color combinations of his rug designs entirely by adding or changing 1 color only. Apparently, there is so far no clear recognition of the optical-perceptual conditions involved.

Interaction of Color by Josef Albers

It's pretty powerful and shows how color perception can be manipulated in interesting ways.

We might not know exactly why it happens optically, but we know that the substitution of a single color affects the relationship of an entire color series/palette which causes a substantial shift in designs.

The wiki page on the Bezold Effect shows red bars on top of a black column and a white column. When we add a way to adjust the darkness of one of the columns we can see the effect in action.

The red looks darker on dark colors, and becomes brighter as it lightens, despite the red bars never changing.