Gödel, Escher, Bach: An Eternal Golden Braid (1979) by Douglas Hofstadter, is a book about the intellectual themes common to the lives and the works of the logician Kurt Gödel, the artist M. C. Escher, and the composer Johann Sebastian Bach, and shows the thematic connections among mathematics, symmetry, and intelligence. Through short stories, illustrations, and analyses, the book explains how systems acquire meaningful context from the "meaningless" elements that compose a system; self-reference and formal rules; isomorphism; the meaning of communication; how knowledge can be represented and stored; the methods and limitations of symbolic representation; and the notion of "meaning".