“You kill me, my boy. That attitude of yours has always killed me,” Shi Qiang said, sticking up a thumb.

The leaf where Shi Qiang lived was at the top of the tree. It was a spacious house, and was fully equipped with facilities for comfortable living. It had a gym, and even an indoor garden with a fountain.

He said, “The fleet gave me these temporary living quarters. They said I can buy a better leaf with my retirement money.”

“Does everyone have so much space to live in these days?”

“Probably. This kind of structure is the best use of space. A big leaf is equivalent to an entire building from our era. But mainly it’s because there are fewer people. Far fewer, ever since the Great Ravine.”

“But Da Shi, your country is in space.”

“I won’t be going there. I’m already retired, you know.”

Luo Ji’s eyes felt more comfortable here, largely because most of the information windows in Shi Qiang’s house were closed, although there were scattered flashes in the walls and on the floor. Shi Qiang tapped an interface on the floor with his foot, turning one wall entirely transparent and unfurling the night city before their eyes. It was a dazzling, giant forest of Christmas trees chained together by the lights of the traffic.

Luo Ji went over to the sofa, which was hard as marble to the touch. “Is this for sitting?” he asked. At Shi Qiang’s affirmative, he sat gingerly down on it, only to feel like he was sinking into soft clay. The sofa’s cushions and backrest adapted to a person’s body, forming a mold completely in sync with their body shape, keeping pressure to a minimum.

His vision from the slab of iron ore in the Meditation Room of the UN Building two centuries ago had become reality.

“Do you have any sleeping pills?” he asked. Now that he was in a space that felt safe, exhaustion hit him.

“No, but you can buy them here,” Shi Qiang said, and operated the wall again. “Here. Nonprescription sleeping pills. This one, River of Dreams.”

Although Luo Ji thought he would witness some sort of high-tech hardware-over-the-network transmission, the reality was much simpler than he imagined. In a few minutes, a small, flying delivery van pulled up outside the transparent wall and delivered the medicine through the portal that had just opened up with a slender mechanical arm. Luo Ji took the medicine from Shi Qiang. It was a traditional box without any active display. The instructions said to take one pill, so he opened the pack, took one out, and reached out for the glass of water on the coffee table.

“Wait a moment,” Shi Qiang said, taking the box out of Luo Ji’s hands and reading it carefully before returning it to him. “What does this say? The one I asked for was called River of Dreams.”

Luo Ji saw a long string of complicated English-language drug names. “I don’t recognize it. But it’s certainly not River of Dreams.”