Lincoln often said that there was no act which was not prompted by some selfish motive. One day, he was riding in a stage and was discussing this philosophy with a fellow passenger when the stage rumbled past a ditch filled with mud and mire. A small pig, caught fast in the muck, was squealing and struggling to free himself. Many persons in the stage laughed heartily, but Lincoln, then a lawyer, asked the driver to stop for a few moments.
Leaping from the stage, he walked to the ditch and picked the little animal up, setting it on the solid road.
"Now, you cannot say that was a selfish act," said the passenger with whom he had been talking.
"Extremely selfish," said Lincoln. "If I had left that little fellow in there the memory of his squealing would have made me uncomfortable all day. That is why I freed him."
林肯常說，任何行為，動機都在於自私。有一天，他搭驛馬車，正和另一搭客談到這信念，馬車經過一條滿是泥濘的溝渠。一隻小豬陷身泥濘之中，嚎叫着，掙扎着。馬車上許多人都開懷大笑，當時做律師的林肯卻請車夫把馬車稍停一會。
他跳下馬車，走到溝渠前，把小豬提起來，放在結實的馬路上。
那個正和他辯論「自私」話題的搭客說：「這可不能算是自私行為了吧。」
林肯回答：「自私得很。假如我不理那小傢伙，就會整天想到他在嚎叫，整天心裏不安樂。所以我把他救起來。」