 A phonograph dubbed "Record Player X" destroys itself by playing a record titled "I Cannot Be Played on Record Player X" (an analogy to Gödel's incompleteness theorems), an examination of canon form in music, and a discussion of Escher's lithograph of two hands drawing each other.To describe such self-referencing objects, Hofstadter coins the term "strange loop"—a concept he examines in more depth in his follow-up book "I Am a Strange Loop".To escape many of the logical contradictions brought about by these self-referencing objects, Hofstadter discusses Zen koans.