Of the inner, or intercalary chapters, of his classic of American literature, John Steinbeck wrote,

With the rhythms and symbols of poetry one can get into a reader—open him up and while he is open introduce—things on an intellectual level....It is a psychological trick if you wish, but all techniques of writing are psychological tricks.

Chapter 3 of Steinbeck's narrative presents a poetic representation of the tenacious migrants in search of a better life in California. The turtle is determined on his path,

All over the grass at the roadside a land turtle crawled, turning aside for nothing, dragging his high domed shell....

Along the way, his body picks up oat seeds, and after he is knocked around by the truck, the turtle struggles, but finally rights himself. In the process, he has deposited a "wild oat head" onto the earth and three of the spearhead seeds stick in the ground. Unconsciously, the turtle sows these seeds as his cumbersome shell drags dirt over them. Then, this persevering creature continues on his way.

Much like the turtle who endures, the Joads and the other Okies migrate for hundreds of miles with many obstacles in their way. In Chapter 20, for instance, the Joads must continue on as they are turned away by men who refuse to allow any "Okies in this town." As they drive away, Tom expresses anger at the cruelty of the men of Tulare, but Ma soothes him, telling her son that they are a people who will endure and continue to people the world:

"You got to have patience. Why, Tom--us people will go on livin' when all them people is gone . . . We're the people that live. They ain't gonna wipe us out. Why we're the people--we go on."