Favored metaphors change over time, but—and this is less often appreciated—that does not simply mean that one supplants the other. The concept of “vitalism” might be traced back to the Aristotelian soul and is generally regarded as obsolete in biology today, but in fact we’ll see that it still survives in cryptic forms, most particularly in the way

So long as we insist that cells are computers and genes are their code, that proteins are machines and organelles are factories, the picture that emerges is a clumsy marriage of the mechanical and the anthropomorphic. Life becomes an informational process sprinkled with invisible magic.