A river runs through it is actually a story about growth and affection, but once it is connected with the big river where two brothers live together day and night, the context of this life theme will gradually become clear and no longer worrying. For the two brothers, their pastor father and Dahei River set the tone for their lives. Their father can be said to be an intellectual and gave them a strict early education, especially Norman. He asked Norman to write succinctly like a Scot, and kept compressing chapters. Although Norman hated it, it laid the foundation for him to become a talented student at Dartmouth College. Meanwhile, their father taught them how to become fishermen. They have been familiar with their superb fishing skills since childhood, and they can't put it down. Especially for Paul, when Norman asked him what he wanted to be when he grew up, he said he wanted to be a fisherman who fished with flies, but unfortunately there was no such job. But Paul's mind is free and unrestrained, and he is more willing to do what he wants, regardless of any rules. He can abandon the fishing skills given by his father and throw a line to attract fish in his own way; He can encourage Norman to risk his life and drift with him in the dark, and finally they succeed. He can hang out in the bar with his favorite Indian girl, regardless of the rule that Indians are not allowed in the bar; He can go to "Lolo" to gamble, which is what an upright and rigorous father does not want his son to do; Even if Paul finally died and his right hand bone was broken by a gangster, I don't think he felt wronged. As Norman said, Paul has strong qualities. However, Paul will never leave Montana again, because he can't live without the big black and he loves fishing.