The really valuable thing is intuition.

Although similar to many of Einstein's comments about the importance of intuition and imagination, no sources for this can be found prior to The Psychology of Consciousness by Robert Evan Ornstein (1973), p. 68, where there is no mention of where the quote was originally made. A number of early sources from the 1980s and 1990s attribute it to The Intuitive Edge by Philip Goldberg (1983), which also provides no original source.