The Curry triangle, also sometimes called the missing square puzzle, is a dissection fallacy created by American neuropsychiatrist L. Vosburgh Lions as an example
of a phenomenon discovered by Paul Curry. The figure apparently shows that a triangle
of area 60, a triangle of area 58 containing a rectangular hole, and a broken rectangle
of area 59 can all be formed out of the same set of 6 polygonal pieces. The explanation
for this lies in the inaccuracy of the initial subdivision. In the diagrams, the
small and large right triangles are similar, hence they cannot have perpendicular
sides of lengths 
and 
,
respectively, as apparently shown in the drawing.
