To divide a cube into two other cubes, a fourth power or in general any power whatever into two powers of the same denominationabovethesecond isimpossible, and Ihave assuredly found anadmirable proof of this, but the margin is too narrow to contain it.

-Fermat, Pierre de
Scribbled note in the margins of his copy of Diophantus's Arithmetica. He did not live to provide the promised proof, and the conjecture became famous as Fermat's Last Theorem. In 1993  Andrew Wiles, a British mathematician, claimed to have discovered the proof.

Architecture is an art which is basically geometrical. The cube is the basis of architecture because the right angle is necessaryöthe steps of a staircase consist of vertical and horizontal planes and the corners of rooms are nearly always right angles.We need right angles. 542

-Mallet-Stevens, Robert
  'Architecture and Geometry', in Bulletin de la Vie Moderne, Paris.