Albert Einstein.  Geometrie und Erfahrun.  Berlin:  Julius Springer,  1921.  1st edition.  20  8vo.  Paper wrappers. Very good condition. 
First Edition. Weil 115. From the Dictionary of Scientific Biography, vol 4, p 330:

"During these years Einstein was also concerned to clarify misconceptions about  the theory of relativity and to present his views on natural sciences on a less  abstract level. Among his efforts in this direction, one particularly beautiful  lecture must be mentioned. In 1921, at the Prussian Academy's commemorative  session honoring Frederick the Great, Einstein delivered a lecture on geometry  and experience in which he summed up his views on the geometrization of physics  and relativity and the relation of mathematics to the external world. Here he
gave his famous answer to the puzzling question of why mathematics should be so  well adapted to describing the external world: 'Insofar as the Laws of  Mathematics refer to the external world, they are not certain; and insofar as
they are certain, they do not refer to reality'"  $275