the time when we tend to notice that we need toilet paper tends not to be the moment when we are in a position to buy it. - Gary F. Marcus

Biology doesn't know in advance what the end product will be; there's no Stuffit Compressor to convert a human being into a genome. But the genome itself is very much akin to a compression scheme, a terrifically efficient description of how to build something of great complexity-perhaps more efficient than anything yet developed in the labs of computer scientists (never mind the complexities of the brain, there are trillions of cells in the rest of the body, and they are all supervised by the same 30,000-gene genome). And although there is no counterpart in nature to a program that compresses a picture into a compact description, there is a natural counterpart to the program that decompresses the compressed encoding, and that's the cell. Genome in, organism out. Through the logic of gene expression, cells are self-regulating factories that translate genomes into biological structure.

"Repetition sometimes works in poetry, but rarely in prose. The musical provocateur John Cage once wrote a lecture in which a single page was repeated fourteen times, with the refrain "If anybody is sleep let him go to sleep" (Cage, 1961). Midway through, the artist Jean Reynal stood up and screamed, "John, I dearly love you, but I can't bear another minute.

"Sometimes guitar riffs get repeated over and over ("vamping," in the lingo of musicians), but generally there is a soloist proving variation that runs above that background, lest the song sound monotonous. Philip Glass's minimalist compositions (such as the soundtrack to 'Koyaanisqatsi') deviate from much of the classical music that preceded them, with much less obvious movement than, say, the Romantic-era compositions that his work seems to rebel against, yet his works, too, consist not only of extensive repetition but also of constant (though subtle) variation. Virtually every song you've ever heard consists of exactly that: themes that recur over and over, overlaid with variations."