Compare "There was nothing for Decoud but to remain on the island." The chapter has already compared Charles Gould and Decoud in terms of their reactions to seeing the "cruel futility of things." While Decoud's reaction is an ultimate withdrawal from the fray, Charles Gould's is presented here: though deprived of any moral basis for his actions, he will go on acting, as a moral automaton. Or rather as a "buccaneer," i.e., in the name of sheer selfish gain without regard to morality, as the next paragraph makes clear.