How does Dolphus Raymond explain Dill's crying?

From the text:

He jerked his head at Dill: “Things haven’t caught up with that one’s instinct yet. Let him get a little older and he won’t get sick and cry. Maybe things’ll strike him as being—not quite right, say, but he won’t cry, not when he gets a few years on him.”

“Cry about what, Mr. Raymond?” Dill’s maleness was beginning to assert itself.

“Cry about the simple hell people give other people—without even thinking. Cry about the hell white people give colored folks, without even stopping to think that they’re people, too.”