Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution. It is, strictly speaking, a real factor in scientific research.
Source, in full
Cosmic Religion : With Other Opinions and Aphorisms (1931) by Albert Einstein, p. 97; also in Transformation : Arts, Communication, Environment (1950) by Harry Holtzman, p. 138. This may be an edited version of some nearly identical quotes from the 1929 Viereck interview below.