He was beaten (he knew that); but he was not broken. He saw, once for all, that he stood no chance against a man with a club. He had learned the lesson, and in all his after life he never forgot it. That club was a revelation. It was his introduction to the reign of primitive law, and he met the introduction halfway. The facts of life took on a fiercer aspect and, while he faced that aspect uncowed, he faced it with all the latent cunning of his nature aroused.

This quotation is taken from late in Chapter 1, “Into the Primitive,” just after Buck has been beaten repeatedly by one of his kidnappers. Each time he is clubbed, Buck leaps up to attack again, until finally the man knocks him unconscious. This incident is Buck's introduction to a new way of life, vastly different from the pampered existence that he led in the Santa Clara Valley. There, civilized law, and civilized morality were the ruling forces—symbolized by the fact that his first master, Judge Miller, is a judge. In the wild, though, Buck comes to terms with “the reign of primitive law,” in which might makes right, and a man with a club (or a powerful dog) can do as he pleases to weaker creatures. In this scene, Buck is mastered by the man with the club, but he learns his lesson well and soon comes to master others.