But our genes are more like the dictionary of words available for writing the book of instructions—or, we shall soon see, the set of subroutines that are called by the master program. As Ridley says, the list of words in David Copperfield is almost the same as the list of words in The Catcher in the Rye. Both draw upon the vocabulary of an educated native speaker of English. What is completely different about the two books is the order in which those words are strung together.