Langman and Cohn have written a paper entitled "If the immune repertoire evolved to be large, random, and somatically generated, then em leader " This paper uses reductionist logic to prove that the minimal model of immunity proposed by Langman and Cohn is the only reasonable description of the workings of the immune system. Here we analyze the logic behind this model and show that the complexity of the real immune system contradicts the teachings of Langman and Cohn.