Curry Triangle. This seeming paradox, devised in 1953 by the US magician Paul Curry (1917-1986), is an example of a 'missing square problem', also known as a 'dissection problem'. The triangle at left appears to have an area of 60 units, but when rearranged at centre and at right, the area appears to be 58 or 59 units. This is caused by an optical illusion, as the larger (red and pink) and smaller (yellow and blue) triangles have different angles forming the sloping side (hypotenuse). Hence the true area is 59 units (right), while the sides of the constructed triangles (centre and left) are not straight, causing the incorrect calculations.