Why do we say A man’s got to do what a man’s got to do?

Casey said quickly, “I know this – a man got to do what he got to do. I can’t tell you. I don’t think they’s luck or bad luck. On’y one thing in this worl’ I’m sure of, an’ that’s I’m sure nobody got a right to mess with a fella’s life. He got to do it all hisself. Help him, maybe, but not tell him what to do.” Alphabetical list of expressions

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