The Oxford Murders

“Wait, wait,” she whispered, glancing around. “Do you make love on te

She drove in silence, smiling to herself and turning her head slightly to look at me from time to time. At a set of traffic lights, she stretched out her hand and stroked my face.

“So the matter of John and Sammy…” I said.

“I had nothing to do with it,” she said, laughing, but she sounded less convincing than earlier. “Don’t mathematicians believe in coincidences?”

We parked in a little sidestreet in Summertown and climbed the two floors up to Lorna’s place, which was the attic flat of a large Victorian house. She opened the door and we started kissing again as soon as we were inside.

“I’m going to the bathroom for a minute, OK?” she said and headed along the corridor towards a door with a frosted-glass pane.

I waited in the small sitting room and looked around. It was charmingly untidy, full of a motley assortment of possessions-holiday snaps, soft toys, film posters and a large number of books crammed into a small bookcase. I leaned over to read some of the titles. They were all crime novels. I glanced in at the bedroom. The bed was neatly made, with a floor-length bedspread, and an open book lay face down on the bedside table. I went to take a look. I read the title and name above it, frozen with astonishment: it was Seldom’s book on logical series, full of furious underlining and illegible notes in the margins. I heard the sound of the shower and, a little later, Lorna padding along the corridor in bare feet and her voice calling me. I put the book back as I found it and went to the sitting room.

“So,” she said from the door, showing me that she was already naked, “still got your trousers on?”

Seven

There’s a difference between the truth and the part of the truth that can be proved. In fact this is one of Tarski’s corollaries to Godel’s theorem,” said Seldom. “Of course, judges, pathologists, archaeologists all knew this long before mathematicians. Think of any crime with only two possible suspects. Both of the suspects know the part of the truth that matters, i.e. it was me or it wasn’t me. But the law can’t get to that truth directly; it has to follow a laborious, indirect route to gather evidence: interrogations, alibis, fingerprints and so on. All too often there isn’t enough evidence to prove either one suspect’s guilt or the other suspect’s i

Seldom paused for a moment and leaned over to the neighbouring table for a paper napkin. I thought he was going to write out a formula on it, but he simply wiped his mouth quickly and went on: “Godel showed that even at the most elementary levels of arithmetic there are propositions that can neither be proved nor refuted starting from axioms, that are beyond the reach of these formal mechanisms, and that defy any attempt to prove them; propositions which no judge would be able to declare true or false, guilty or i

We were the last two people left at the long Fellows table at Merton. Facing us in an illustrious row hung portraits of distinguished former alumni of the college. The only name I recognised on the bronze plaques beneath the portraits was T.S. Eliot. Around us, waiters discreetly cleared away the plates of dons who had already gone back to their lectures. Seldom grabbed his glass of water before it was removed and had a long drink before continuing.

“In those days I was a fervent Communist and was very impressed by a sentence of Marx’s, from The German Ideology, I think, which said that historically humanity has only asked itself the questions it can answer. For a time I thought this might be the kernel of an explanation: that in practice mathematicians might only be asking the questions for which, in some partial way, they had proof. Not, of course, unconsciously to make things easier for themselves but because mathematical intuition-and this was my conjecture-was inextricably linked with the methods of proof, and directed in a Kantian way, shall we say, towards what can either be clearly proved or clearly refuted. That the knight’s moves involved in the mental operations of intuition were not, as was often believed, sudden dramatic illuminations but modest, abbreviated versions of what could always be reached eventually with the slow, tortoise-like steps of a proof.”

“I met Sarah, Beth’s mother, at that time. She had just started studying physics and she was already engaged to Joh