“I think I’ve got an idea about how the series continues-about the next symbol in the series,” said Seldom slowly. “But it doesn’t enable me to infer anything about the next murder.”
“All the same, wouldn’t even that-the symbol-be a great help to Inspector Petersen? Is there any other reason why you don’t want to tell him?”
“Come on, let’s go for a walk in the park,” he said. “I’ve got a few minutes before my student’s lecture and I need a cigarette.”
There were policemen still at the entrance dealing with the fingerprints on the glass, so we left by one of the back doors. En route we passed Podorov. He greeted me halfheartedly and stared fixedly at Seldom, as if hoping Seldom would recognise him. We walked around the Physics Laboratory and took one of the gravel paths leading into the University Parks. Seldom smoked in silence, and I thought for a moment that he wasn’t going to say anything more.
“Why did you become a mathematician?” he asked suddenly.
“I don’t know,” I said. “Perhaps it was a mistake. I always thought I’d do a humanities degree. I suppose what attracted me was the kind of truth that theorems contain: timeless, immortal, self-contained, and yet absolutely democratic. Why did you choose mathematics?”
“Because it harms no one,” said Seldom. “Because it’s a world that has nothing to do with reality. You know, terrifying things happened to me when I was very young, and have happened throughout my life, as if they were signs. They’ve been intermittent, but still too frequent and too terrible for me to ignore.”
“What type of signs?”
“Let’s say…I noticed the chain of events provoked by any small action on my part in the real world. They were probably coincidences-just unfortunate coincidences-but they were so devastating that they almost brought me to a complete standstill. The last of these signs was the accident in which my wife and two closest friends died. I don’t know how to say this without sounding ridiculous but, from very early on, I noticed that the conjectures I made about the real world always came true, but by strange paths and in the most horrible ways, as if I were being warned that I should keep away from the world of people. I was utterly terrified during my adolescence. It was then that I discovered mathematics. For the first time in my life I felt I was on safe ground. For the first time I could follow a conjecture, as determinedly as I liked, and when I wiped the blackboard clean, or crossed out a page where I’d made mistakes, I could start again entirely from scratch, without unexpected consequences. There is a theoretical parallel between mathematics and criminology; as Inspector Petersen said, we both make conjectures. But when you set out a hypothesis about the real world, you inevitably introduce an irreversible element of action, which always has consequences. When you look in one direction, you stop looking in all the others. When you follow a possible path, you follow it in real time and it may then be too late to try a different one. What I most fear is not, as I told Petersen, getting it wrong. What I most fear is what has happened throughout my life: that what I’m thinking will come true in the most horrific way.”
“But saying nothing, refusing to reveal the symbol, is that not in itself, by omission, a form of action which might also have incalculable consequences?”
“Perhaps, but for now I’d rather take that risk. I’m not as keen as you to play the detective. And if maths is democratic, the next symbol in the series will be obvious to all. You, Petersen himself, you all have the necessary elements to find it.”
“No, no,” I objected, “what I meant was that in maths there’s a democratic moment, when the proof is set out line by line. Anyone can follow the path once it’s been marked out. But there is of course an earlier moment of illumination, what you called the knight’s move. Only a few people, sometimes only one person in many centuries, manage to see the correct first step in the darkness.”
“A good try,” said Seldom
“One person in centuries’ sounds very dramatic. Anyway, the next symbol I have in mind is very simple. It doesn’t really require mathematical knowledge. But establishing the relationship between the symbols and the murders is more difficult. It may not be such a bad idea to have a psychological profile. Well,” he said, glancing at his watch, “I should head back to the Institute.”
I said I wanted to walk on a bit further and he handed me the card that Petersen had given him.
“Here’s the address of the police station. It’s opposite a shop called Alice in Wonderland. We could meet there at six, if that suits you.”
I continued along the path and stopped in the shade of some trees to watch the unfathomable mystery of a game of cricket. For several minutes I thought I was witnessing the preparatory stages before the game, or else a series of failed attempts to start. But then I heard enthusiastic applause from some women in large hats sitting drinking punch at one end of the field. I’d obviously missed a wonderful piece of play. Perhaps the game had reached a decisive moment just then, before my very eyes, but all I could see was an exasperating lack of action.
I crossed a small bridge-on the other side, the park lost some of its neatness-and walked along the river through yellowing pastureland. Every so often I saw couples in punts on the river. There was an idea somewhere there, close by, like the buzzing of an insect that you can’t see, an intuition about to be clarified, and for a moment I felt that if I were in the right place perhaps I’d be able to glimpse an edge and grab hold of it. As in maths, I wasn’t sure whether to persist and try to conjure it up, or forget about it, deliberately turn away and wait for it to appear of its own accord. Something in the tranquillity of the landscape, the gentle splashing of oars hitting water, the polite smiles of the students in the passing boats, seemed to dilute the tension. In any case it wasn’t here, I realised, that the key to deaths and murders would be revealed to me.
I took a short cut through the trees back to my office. My Russian colleague had gone to lunch, so I decided to ring Lorna. She sounded cheerful and excited. Yes, she had news, but first she wanted to hear mine. No, Seldom had told her only that a strange message had appeared stuck to a window. I told her how I had found the note, described the symbol and then repeated as much as I could remember of the conversation with Inspector Petersen. Lorna asked a few more questions before telling me what she knew: Ernest Clarck’s body hadn’t been transferred to the police morgue; instead, the police pathologist had carried out the post-mortem at the hospital, with one of the doctors there. She’d managed to get the doctor to tell her about it over lunch. “Was that difficult?” I asked with a pang of jealousy. Lorna laughed. Well, he’d invited her to sit at his table several times before, and this time she’d accepted.
“Both he and the pathologist were nonplussed,” said Lorna. “Whatever Mr Clarck was injected with, it left no trace-they found absolutely nothing. The doctor said he too would have signed a certificate stating it was a death from natural causes. Now, there could be an explanation: there’s a fairly new drug, extracted from the mushroom Amanita muscaria, and no reagent to detect it has yet been found. It was presented last year at a closed medical conference in Boston. The strange thing-the most interesting thing-is that forensic pathologists have never publicised the existence of the drug. Apparently, they all swore never even to reveal its name. Wouldn’t that indicate that the police should look for the murderer among forensic pathologists?”
“Or among the nurses who have lunch with them,” I said. “As well as the secretaries who took the minutes at the conference, the chemists and biologists who identified the chemical and maybe the police too. They must have been informed of the drug’s existence.”