"Do you know what I've noticed, Professor Callahan?"
"Is it that you've stopped using my first name?"
"Nothing. What have you noticed?"
"People seem to be acting... differently. I can't quite place it, but something seems amiss."
"They only act differently when you're around."
"Well, that seems a bit inconsistent. Why would they do that?"
"Because-- ... It's a bit of a delicate matter to broach, methinks."
"Stop walking for a moment." They stopped. "Do you see that tower that we're approaching?"
This was met with a quisitive look. "Is this a rhetorical question?"
"Yes, it's a rhetorical question. Do you know when that tower was built?"
"I don't recall. It never really concerned me all that much."
"Well, if I wanted to find out when it was built, what would I do?"
"I suppose that you'd have to track down the records for when the contract work happened. It's probably on record at the university library or something."
"Well, it's not, and it's not on record at the city, either, and there's really quite an interesting reason behind that."
"Well, it sounds like you're about to tell me what it is."
"Yes. It just appeared one day."
"That is unusual. ... Oh, wait, I remember now. I had to put it there, since it hasn't been built yet."
"Doesn't that seem a bit unusual?"
"Well, it's not that commonly done, but I do like the peace and quiet that it provides."
"I-- No, I mean the whole 'doing magic' thing."
"You! You've been doing magic and it's really weird because magic isn't supposed to be real and also you're a physicist."
"I don't know what you mean. I wouldn't have time for it, anyway: I've been too busy with my research."
"Then what's with the robes?"
"They're traditional professorial garb."
"And the book?"
"These are my notes. I use them for reference in case I forget a detail. Wouldn't I feel silly if I needed to get somewhere and forgot how?"
"So, there are maps in there?"
"Don't be silly. Maps are for travelling, which, I've discovered, is no longer necessary."
"Wait.... Is this how you get up into the tower with no doors?"
"Well, 'up' isn't really the right way to put it, but yes."
"And you're sure that it's not magic, then?"
"It's not magic; it's just science. Now, if you'll excuse me, I must be getting to the early medieval period." And with that, he vanished.