Hofstadter’s principal thesis is that we ourselves, qua conscious beings, are “emergent self-referential structures”. I Am a Strange Loop thus revolves around two main ideas: the idea of an emergent phenomenon and the idea of self-reference, or of a “strange loop” to use Hofstadter’s technical term.
A strange loop is a phenomenon that involves reference to itself. An artwork, a thought, or a sentence may twist back on to itself and self-refer. Thus, the sentence “this very sentence is written in English” is self-referential, because it refers not to any old sentence, but to itself. A more surprising example explored by Hofstadter (which does not employ the demonstrative expression “this very”) is the sentence “‘preceded by itself in quote marks yields a full sentence’ preceded by itself in quote marks yields a full sentence”. (Think about that for a moment.) Many other self-referential phenomena are discussed throughout the book, including self-videotaping videos, self-proving mathematical proofs, Escher’s self-referential paintings, etc.
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