Why does Huck decide it is useless to argue with Jim?

Jim has a very simple yet effective logic which Huck can't quite contend with. Although Jim has never been to school, his logic has this bizarre merit even though he is wrong. An example is when Huck tries to explain to Jim that Frenchmen speak a different language. Jim is surprised by this and cannot understand why all men would not speak the same language. Huck tries to make the analogy that a cat and a cow do not speak the same language, so neither should an American and a Frenchman. Jim then points out that a cat and a cow are not the same species, but Frenchmen and Americans are. He concludes that Frenchmen should therefore speak the same language he does. At this point Huck gets frustrated and gives up trying to argue with Jim.

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