Although Dave is a product of the more modern world, Dave's father represents the old-time values of the past. After Luster has spent the day at school, he finally realizes that he can no longer hold his son back: The father recognizes that modern schooling has its advantages and that Dave must get an education in order to get out of the drudgery and hard life of farming.
"I'm behind. I'm a little man."
But Luster also wants Dave to remember the positive aspects and solid moral values of his own time. Luster believes in hard work, honesty, and honoring his word. Luster is releasing Dave into the hands of the trusted teacher who Luster knows will lead his son to a better life. But Luster also wants Dave to remember to pay his debts, such as completing the chores he owes Professor Herbert; to be honest, as Dave has done in describing the trouble he got into by climbing the cherry tree and by his truthful description of school and his teacher; and not to "bother the snakes," since Luster has
... a tender heart beneath his ribs for snakes, but not for man! Pa won't whip a mule at home. He won't whip his cattle.
"Man can defend hisself," says Pa, "but cattle and mules can't. We have the drop on 'em. Ain't nothin' to a man that'll beat a good pullin' mule. He ain't got th' right kind o' a heart!"
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