Linked from
The 18 pages that link to Simultaneous contrast, each with the reason it gives.
Color theoryRelated: A color’s appearance shifts with its neighboring colors.
PointillismRelated: Adjacent dots can alter one another’s apparent brightness and hue.
Josef AlbersRelated: Albers used neighboring hues to make identical colors seem different.
GreenRelated: A green patch can look different depending on the hues placed beside it.