Perseus Academic: Godel, Escher, Bach by Douglas R. Hofstadter

“EGB’s greatest accomplishment is to show that the austere and frigid world of pure mathematics is by no means as remote from the two worlds of art and music as the humanist in the street believes it to be.… Hofstader guides his uninitiated reader through level after level of the mathematical funhouse, not only explaining its layout but also conveying a sense of the wonder and the beauty that do, in fact, reside there.”
— Walter Kendrick, Village Voice

“I cannot begin to do justice to the wealth of suggestive analyses in Hofstader’s book. In its 700 odd pages, he reviews a wide range of mathematical-type operations: ‘recursion,’ (an entity embedded within a larger version of the same entity, like a story within a story); ‘strange loops’ (systems in which one can start at a point and then work through a number of levels—only to find oneself at the beginning again); systems reflecting upon or referring to themselves, and numerous others. Patiently he explains and explores their manifestations not only in their original, mathematical guise but also in the analogous realms of music, verbal play, and pictures.”
— Howard Gardner, Psychology Today