Abraham Lincoln’s explanation of psychological egoism in the fable about piglets demonstrates that this theory is likely to be true. Indeed, Lincoln demonstrated it with his own experience when he saved the piglets from the swamp. He stated that he saved them not for the benefit of their good but to ease his consciousness.
In such a manner, the motivation to do such an altruistic action as saving the piglets was not motivated by the benefit of others but by self-interest, which proves the theory of psychological egoism. Moreover, the very context of the episode might be a self-interest motivation for Lincoln since such action helped him prove his point in the argument with Baker and gain respect from his opponent.
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