Chapter Twelve

Laurence stood still for a moment, questioning himself.

Before he had arrived at the philosophy department on the edge of the university campus, he had been expecting something else entirely. Philosophy conjured images of quiet contemplation. Laurence recalled kneeling by the hearth in their small house while his father sat reading in an armchair. Dust in the air; warmth on his face; a safe silence undisturbed beyond the gentle crackle of the fire and the quiet turning of pages. And yet the building before him now—a newly built block of polished black marble, sandstone, and glass—looked like a place more suited to laboratory experiments than those carried out within minds.

The doors slid apart as he stepped forward.

He was expected, and one of the secretaries in the main office pointed him in the right direction. He wandered down a corridor that wouldn't have been out of place in a modern office block—clean carpets; pine-scented air freshener; anonymous modern art prints hanging between the wooden doors—and finally reached the office of Professor Robin Nelson. It had been left slightly ajar in anticipation of his arrival, but he rapped gently with his knuckles anyway.

"Come in."

He pushed the door wider. The room contained an oak desk, with papers and used mugs strewn around the computer there. The shelves lining the walls were crammed tightly with books and even more sheafs of paperwork, some of it occluded by randomly placed trinkets and photographs. A tattered rug had been spread out near the door. This was more like it, Laurence thought happily. The office felt lived in, as though the occupant, upon being granted a sterile new office, had made a concerted effort to transport every last crumb of dust across from their old one.

Nelson stood up and walked around the desk, extending a hand. Laurence shook it. The professor had a slightly foppish swathe of brown hair and was wearing a red velvet jacket over a checked shirt. He was only in his thirties, Laurence guessed, which seemed young to be a professor, never mind head of the department.

Nelson seemed aware of that himself, and even slightly embarrassed by it.

"It's more an administrative position than anything else," he explained as he cleared a seat for Laurence. "Or a prison sentence. All it really means is lots of extra work and headaches. The role changes hands every five years, and the smarter ones find a way of avoiding it."

Laurence glanced at the wall of books. He figured Nelson was pretty smart.

"How long do you have left to serve?" he said.

"Three years, ten months, two weeks, and two days."

Laurence laughed as he sat down.

"I'll try not to take up too much of it," he said. "Especially given why I'm here. I'm sorry for your loss."

"Thank you." Nelson looked slightly pained as he returned to his own seat. "I can't really take that though. I didn't know Professor Hobbes well at all. He actually retired before I started here—although he did return for guest lectures on occasion, so we met in passing. But I can tell you that he was very well liked for the most part. Everyone here is shocked."

Laurence frowned.

"Well liked for the most part?"

"Oh—just a turn of phrase, really. As a person, is what I meant. He was a good guy—and a brilliant teacher too, by all accounts, which is what matters most. Devoted to teaching. Generally speaking, his students loved him. But one particular subject he taught—the one he specialized in—can be difficult for some people to process. It can upset people."

"Determinism?"

"Yes."

Laurence had spent a little time reading up about it last night and understood the basics of the arguments well enough. But there was often no harm in appearing to know less than you did.

"Can you run me through it?"

Nelson looked delighted.

"Yes, of course! Well, I can try—it's not my area. But the basic idea is a very simple one. Here."

He searched for something in the mess on his desk. He found a pen, held it up for a moment, and then dropped it on the desk. Laurence watched as it clattered against the wood.

"Now," Nelson said. "Why did the pen fall?"

"Gravity."

"Exactly. The laws of physics—everything in the universe obeys them. Every effect has a cause." Nelson touched the side of his head. "But the human brain is part of the universe. It's made up of the same basic matter, and so it follows the exact same physical laws. Which means that every action you take, every decision you make, is caused by the state of your brain immediately before it. And that state is caused by the one before that. And so on, meaning that all your decisions are predetermined. There's a famous thought experiment called Laplace's demon…?"

Laurence had heard of it. But he waited.

"Okay," Nelson said. "So. Imagine a creature—a demon—that understands all the physical laws in the universe. It also knows the exact state of every atom at a single moment in time, all the way down to the smallest part. It follows that demon would be able to work out everything that had ever happened or ever would. All of it would be inevitable, from the first moment of the universe to the very last."

Laurence considered that. It made him think of the case file he'd been looking through earlier. Michael Hyde's red patchwork car angled across the pavement. Christopher Shaw, a boy who had simply been in the wrong place at the wrong time.

An attack that could have happened to anyone.

"What about random chance?" he said.

"There's no such thing." Nelson shook his head. "It only feels that way because we don't have the knowledge the demon has. In physics, some events at a really small level do appear to be random—but that doesn't help you and me. All it means is that our actions are caused or random. Which doesn't leave much room for us to be doing anything."

"You mean free will?"

"That's right. Do you drink, Detective?"

Laurence raised an eyebrow. "Is it that obvious?"

"Not at all." Nelson laughed. "It's just an example, because I certainly do. But on an evening when you're deciding whether to open that bottle of wine or not, it might feel like you're free to make up your mind either way. But you aren't. What will happen will happen. Because what happens was always going to happen. You had no more choice than the pen did just then."

"That's depressing."

"In many ways."

"And this was what Professor Hobbes taught?"

"Part of it," Nelson said. "What I just described is the materialistic approach to determinism—based on science. But there are others. One logical approach, for example, argues that all statements have to be true or false, even ones about the future. But another is based on the idea of God. That was Professor Hobbes's specialism."

"Oh?"

"Many religions consider God to be omniscient—all-knowing. And if God knows the future, then the future can't be changed."

"That's depressing for God too."

Nelson laughed again.

"Yes. It would reduce the universe to the equivalent of a bauble on his table, wouldn't it? Nice to look at from time to time, perhaps, but not exactly full of surprises. Or the kind of moral choices that God is, let's say, traditionally supposed to be interested in."

"Yes. Maybe I should stop arresting people."

"Oh, no—don't do that. But actually, yes, the whole subject does open up all kinds of questions along those lines."

"You said it upset people?"

"Sometimes. Especially if they're prone to that kind of thinking. For some people, the idea that you don't have a real choice can feel like it robs the world of meaning and purpose. For other people… well, I suppose you could use it as an excuse to do anything you wanted."

"In which case you were always going to anyway?"

"Yes! Because it was inevitable you would encounter the theory."

Nelson smiled, proud of his teaching.

"Did Professor Hobbes ever get any trouble on that level?" Laurence said. "Hate mail. One of these conflicted students harassing him. Negative attention. Anything like that?"

Nelson thought about it.

"Not to my knowledge. But like I said, he hasn't taught here in years. And all that was before I started working here."

"Could you look into it for me? See if anything has survived?"

"I can try. I mean, I don't think it would be a very long list."

"By chance, my favorite kind of list."

Laurence nodded in thanks and then stood up and walked toward the door. As he did so, Nelson came out from behind his desk.

"Do you really think this has anything to do with what happened to Professor Hobbes?"

Laurence hesitated.

Most likely not, he thought. At the same time, he thought about Laplace's demon. He couldn't shake what he'd been told yesterday and had been lingering in his mind ever since—that from his behavior, it appeared Alan Hobbes had known his death was coming before it arrived.

But if that were true, why had he done nothing to avoid it?

"I don't know," he said. "But thank you for taking the time to talk to me."

As he opened the door, the thought occurred to him.

Although I suppose you didn't have a choice, did you?