Sif blinked, head canted. “A shirt?” she ventured timidly.

“Yes.”

“I don’t know what you mean.”

Falthejn gestured to his arm. “The sleeve of my tunic is a piece of cloth. That cloth is the structure. The greenness of my sleeve is built on the structure of the cloth. So also is our world built on the structure of magic—natural magic, a framework far stronger and more complicated than this fabric.” He took a breath, and saw her nod thoughtfully. “I’ll tell you how our magic fits in sometime later. You know enough, now, that I can answer your question from this morning.”

“Okay.”

“Have you ever walked down a narrow street and felt as though the buildings to either side were closing in on you? The shadows deepening, the air growing heavier?” Falthejn said. Sif nodded. “Why do you think that is?”

Sif took a guess. “Magic?”

The corners of Falthejn’s mouth turned up. “Exactly. Some alleys are dark and closed—in, some rivers are fast and deadly, and some roads are safe and easy to travel, all, in the end, because of magic. Why? Because people think they ought to be.”

Sif blinked. “Is that all?” she said.

“It’s a little more complicated, as in the case of the river, but yes. If there are people to think about a thing, the way they think about it influences its shape in the magical weave of the world, and its shape in the weave influences its shape in the reality we see. If there aren’t people to think about a thing, its shape in the weave is controlled by how people would think about it.”