"Yes, sir," said Wilbur.

"How do they?"

"No, sir," said Wilbur.

"Well, it's simple enough. This star dust shakes together, and pretty soon some of it gets to be one chemical and some of it gets to be another, like water and salt and lime and phosphorus and stuff like that, and it gets together in little combinations and it makes little animals, so little you couldn't see them, and they get together and make bigger animals, and pretty soon they have brains and stomachs—and there you are. This electricity or something that shook the star dust together and made the chemicals, and shook the chemicals together and made the animals—well, it's fierce stuff. It wants to find out all about itself. It keeps making animals with bigger brains all the time, so it can examine itself and write books about itself—but the animals have to be good killers, or something else kills them. This electricity that makes 'em don't care which kills which. It knows the best killer will have the best brain in the long run; that's all it cares about. It's a good sporty scheme, all right. Do you understand that, Doctor?"

"Yes, sir," said Wilbur.

"Everything's got a fair chance to kill; this power shows no favours to anything. If gophers could kill dogs it would rather have gophers; when microbes kill us it will rather have microbes than people. It just wants a winner and don't care a snap which it is."

"Yes, sir."

"Of course, now, you hear human people swell and brag and strut round about how they are different from the animals and have something they call a soul that the animals haven't got, but that's just the natural conceit of this electricity or something before it has found out much about itself. Not different from the animals, you ain't. This tree I'm leaning against is your second or third cousin. Only difference, you can walk and talk and see. Understand?"

"Yes, sir," said Wilbur. "Couldn't we go up to the gypsy camp now?"

Dave refilled the calabash pipe, lighted it, and held the match while it burned out.