Etymology

café wall illusion

Today it means: An optical illusion in which the parallel straight dividing lines between staggered rows with alternating dark and light bricks appear to be sloped rather than parallel. Full definition →

Ask AI about its historyChatGPTClaudePerplexityGoogle AIGrok

The story

Described under its current name in 1973 by Richard Gregory, according to whom this effect was observed by a member of his laboratory, Steve Simpson, in the tiles of the wall of a café at the bottom of St Michael’s Hill, Bristol.

Etymology from Wiktionary, CC BY-SA 4.0.