But Einstein realized that Newton had left something out of the story, because even Newton had written that although he understood how to calculate the effect of gravity, he'd been unable to figure out how it really works.
Men Einstein indså, at Newton havde udeladt noget fra historien, for selv Newton havde skrevet, at selvom han forstod, hvordan man udregnede tyngdekraftens effekt, havde han været ude af stand til at finde ud af, hvordan den virkelig virker.