Coyote wagged his head mischievously. “I had to bring it in, or else otherwise you were going to bury me in caliche blanco, weren’t you. We’re out here on the road, we’ve got some seeds but not much else— certainly not millions of tons of new caliche deposits! And we actually need the hydrogen peroxide and the pasta too, it’s not just a luxury like lettuce seeds. Tell you what, if you find the truck you can burn its equivalent, and you’ll still have given us fair. If you don’t find it, then you’ll owe us one, I admit it, but in that case you can burn a gift, and then we’ll have given you fair!”

“It’ll take us a week’s work and a bunch of fuel to recover the truck.”

“All right, we’ll take another ten picobars, and burn six of it.”

“Done.” The woman shook her head, baffled. “You’re a hard bastard.”

Coyote nodded and got up to go refill their cups.

Art swung his head around and stared at Nirgal, his mouth hanging open. “Explain to me what just went on there.”

“Well,” said Nirgal, feeling the benevolence of the kava flowing through him, “they were trading. We need food and fuel, so we were at a disadvantage, but Coyote did pretty well.”

Art hefted the white block. “But what’s this get nitrogen, and give nitrogen, and burn nitrogen? What, do you torch your money when you get it?”

“Well, some of it, yeah.”

“So both of them were trying to lose?”

“To lose?”

“To come out short in the deal?”

“Short?”

“To give more than they got?”

“Well, sure. Of course.”

“Oh, of course!” Art rolled his eyes. “But you . . . you can’t give too much more than you get, did I understand that?”

“Right. That would be potlatching.”

Nirgal watched his new friend mull this over.

“But if you always give more than you get, how do you get anything to give, if you see what I mean?”

Nirgal shrugged, glanced at Vijjika, hugged her waist suggestively. “You have to find it, I guess. Or make it.”

“Ah.”

“It’s the gift economy,” Vijjika told him.

“The gift economy?”

“It’s part of how we run things out here. There’s a money economy for the old buy-and-pay system, using units of hydrogen peroxide as the money. But most people try to do as much as they can by the nitrogen standard, which is the gift economy. The Sufis started that, and the people in Nirgal’s home.”