"But he doesn't act like one. I wonder if this is his true shape?"
Harrison shook his head, and lighted his pipe.
"What is there of him?" Cercy asked. "He looks like a man, but he can change into anything else. You can't attack him; he adapts. He's like water, taking the shape of any vessel he's poured into."
"You can boil water," Harrison yawned.
"Sure. Water hasn't any shape, has it? Or has it? What's basic?"
With an effort, Harrison tried to focus on Cercy's words. "Molecular pattern? The matrix?"
"Matrix," Cercy repeated, yawning himself. "Pattern. Must be something like that. A pattern is abstract, isn't it?"
"Sure. A pattern can be impressed on anything. What did I say?"
"Let's see," Cercy said. "Pattern. Matrix. Everything about the Ambassador is capable of change. There must be some unifying force that retains his personality. Something that doesn't change, no matter what contortions he goes through."
"Like a piece of string," Harrison murmured with his eyes closed.