Tortilla Curtain is a story of the intersection of two couples from completely different backgrounds. The first couple is rich, white and privileged who 'care' about the environment and mistreatment of animals but have a complete disregard for illegal immigrants. The second is a homeless Mexican couple who are in a struggle to make pursue their American Dreams.

He tried to reduce it to abstract terms, an accident in a world of accidents, the collision of opposing forces . . .

From the quote above we can see that Delaney is in a state of disbelief and has a sense of denial of his accident. In the accompanying chapter, Delaney narrates his thoughts as he hit the man who was crouched in the bushes like a 'feral animal', another reduction of the human he had hit, as less than.

There are always surprises. Life may be inveterately grim and the surprises disproportionately unpleasant, but it would be hardly worth living if there were no exceptions, no sunny days, no acts of random kindness.

This quote shows hope and belief in humanity. It encompasses the intersection that the two couples meet, random "surprises." With Delaney and his family, they live an upper class life that is for the most part calm and routine. However the surprise in his life is when he hits Candido. Candido and his wife are the unlucky couple who can't catch a break but are are two good hearted people who are met with this "surprise."

Sometimes we felt like we were getting somewhere, but the truth was, like most people, we were just marking time.

The quote above highlights the theme that of a sense of despair is felt by many of the characters.

Low man in the pecking order, even at the dompe. Life is poor here, an old man . . . had told him . . .

Candido had just been hit by a vehicle and is dreaming of a combination of nightmares and memories at this point. He remembers when a garbage man from his village had told him that in their area, life is poor. The struggle that Candido and his wife experience demonstrates the hierarchy and economic disadvantages that afflicts many social communities all over.