Was Macintosh cleverer than him or wasn’t he? There must have been some objective way of telling. Once, he was sure, he had been indubitably cleverer than Macintosh. But he was slowing down. At least, he was afraid he was slowing down. He was pretty certain his brain was of the genus Cerebrum dialectici – a logician’s or child prodigy’s brain, an early-flowering plant already past its best by the age of thirty. His anxiety on the point had developed into a sort of cerebral hypochondria. He was for ever checking his mental performance for symptoms of decline. He borrowed sets of IQ tests from his colleagues, and timed his performances, plotting the results on graphs. When he produced a graph with a curve that went downwards, he assured himself that it was merely a misleading technique; and when he produced one with a curve that went upwards, he told himself sceptically that it must be the result of experimental error.

One symptom of decay, he sometimes thought, was the loss of his opinions. Some people have faith; some people have opinions. Goldwasser had had opinions about almost everything he had ever heard of, and from the age of fourteen he had heard of almost everything in the universe. In the high summer of his cere­bellum he had had the whole of creation divided into two great categories, the things he was for and the things he was against. Now his opinions were falling out like old teeth. His immediate circle of interest had shrunk from the fate of the pi-meson and the theocracy of the gods F and M to an intense consideration of whether or not he was cleverer than Macintosh.

Goldwasser could not see Macintosh out of the window, since he was hidden inside the Gothic fortress of the old Ethics Department, but the noise of the scaffolding being shed from Mac­intosh’s new wing kept him constantly before Goldwasser’s mind. Was Macintosh the cleverer? Was Macintosh’s brain, like his, Cere­brum dialectici? If it was, it was now at the very height of its powers and would subsequently decline at the same rate as his own, if indeed his own was declining. Or was it Cerebrum senatoris – a wise old man’s brain, slowly maturing over the years? If that was what it was, it might have drawn level with Goldwasser’s brain without implying any deterioration in Goldwasser’s own performance. But then again, if it did incline towards Cerebrum senatoris rather than Cerebrum dialectici it would go on improving relative to Goldwasser’s, which was not a very cheering prospect. Goldwasser gloomily agitated his finger in his right ear. The ear had now begun to itch with a definite itch of its own.

Goldwasser suddenly realised he was being watched, and caught a pair of eyes gazing intently at him from well back inside a nearby corridor window. They belonged to Nunn, the Deputy-Director of the Institute. Nunn smiled cheerily, and gave a little wave. Goldwasser started nervously back into the room. He pulled the finger hastily out of his ear, then put it back as if he had intended to have it there all the while for some serious scientific purpose, and began to mess around with the papers on his desk.