“You don’t have to sound so superior either,” Seven said angrily. “I never had an examination like this in my lives, any of them, and I hope I never have another like it in the future, if you’ll forgive the term.”

“Oh, dear Seven, do calm down and try to understand,” Cyprus said. “The so-called past is a source of fresh action and constant creativity just like the future or present—”

“I know that; that isn’t the part that confuses me—”

“So Ma-ah signed the tile now and affected Proteus’ present,” Cyprus said. “A few moments earlier she hadn’t done it in the past, so it couldn’t appear—it hadn’t happened—”

“Ah, I caught you,” Seven cried. “I was always afraid that I would, some day, but I wanted to, too. Now that it’s happened, I wish that it hadn’t. I’ve caught you in the worse kind of contradiction.”

“Don’t look so … soulful,” Cyprus said softly.

Seven didn’t even smile, he just threw Cyprus a reproachful look and said, “You said that Ma-ah hadn’t signed the tile yet, so it couldn’t appear in Proteus’ twenty-third century. But Cyprus, that doesn’t make sense, not if everything happens at once!”

“You can scowl just like Lydia,” Cyprus said.

“All right, take Lydia. She went back and did something new in the past,” Seven said, scowling even harder. “I understand that, I think. Yes, I’m sure I do.” Suddenly Seven got so excited that he blinked off and on until he even made Cyprus dizzy. “I’m getting it, I’m getting it. I think. New things can happen in the past, right? Even as the present happens and keeps happening, the past keeps happening and new events can happen in it. Oh, no, that’s not quite what I mean—”

“You’re getting closer, though,” Cyprus said, excited herself. “Make up an analogy if you have to.”

“An analogy! This entire examination is an analogy, if you ask me,” Seven exploded. But the next thing he knew he had an analogy so real and vivid that he was astounded.

“I must be making it big, so I can see it clearly,” he apologized, grinning. For written across the entire sky in towering, shining letters was the following message:

“Since this is an examination, I’m using the sky as a blackboard,” Seven said proudly. “An extra touch that should earn me a few extra credits, I hope. It’s put rather simply, so I’m sure that it’s clear. Just look at that.”