Sources

Where the facts come from

Every factual claim on this site links to its source. This is the full list.

How we checked

Each fact was written in our own words alongside its source. Our build script stores the text of every source and, for each fact, checks that the key words and figures really appear in it. 88 of 88 checks passed when this site was last built (13 November 2026). Where we couldn’t find a named source saying something, we left it out. Where good sources disagree, we say so and give both.

Where sources differ

The real colours of the dress. Black and blue under good white light (Michael Bach); blue (WIRED); blue and orange, from the photo’s pixels (Bevil Conway, quoted by WIRED).
Who found Benham’s colours first. Gustav Fechner in 1838 (Bach); Benedict Prévost in 1826 (Richard Gregory, quoted by Bach); Charles Benham made the top famous in 1894.
Neon colour spreading. First described by Van Tuijl in 1975 (Bach), though Bach’s reading list includes Varin’s 1971 paper on colour spreading.
Red’s opposite colour. Green in many textbooks; blue-green, says Bach.

How we checked

Where sources differ

All sources (16)