 Whitehead first learned about Einstein’s General Theory of Relativity (GTR) in 1916. He admired Einstein’s new mathematical theory of gravitation, but rejected Einstein’s explanation of gravitation for not being coherent with some of our basic intuitions. Einstein explained the gravitational motion of a free mass-particle in the neighborhood of a heavy mass as due to the curvature of space-time caused by this mass. According to Whitehead, the theoretical concept of a contingently curved space-time does not cohere with our measurement practices; they are based on the essential uniformity of the texture of our spatial and temporal intuition.