This comes up often on hn. Using painting, especially Wayne Thiebaud's as support for the argument is very weak. He's a pop art painter that is known for using exaggerated colors, it's part of the pop art movement's signature style.<p>I would agree that when painting a shadow, you will likely find if you look carefully that it is not black, but in web design color is different and design has different goals to painting. The former is about clarity and function, the latter is expression and feeling.<p>In rebuttal to the argument, there are several hundred years of printing that seemed to have moved western civilization forward quite nicely that was black on white.