It’s not my fate, I realise, to write a restrained, considered book in the third person with immaculate sentences. What a pity. I love lean, tight prose, neat periods that glisten and overlap like the scales on a snake. I love writing that is austere and poised, inflected with the seriousness of past-tense narration, but I understand too that it is a kind of rhetorical trick. A feeling of timeless profundity is created by leaving out what is most messy and most characteristic of ordinary human lives. Gravitas is achieved by exclusion, by not acknowledging the monarch’s farts, the lover’s bad breath, the piles of Lego in the living room. It’s the trick of those photographs of the pyramids that detach them from the sprawl of the Cairo slum. I reread my own pages with a kind of dismay, but it is at least the same kind of dismay I feel when I see my ageing face in the mirror. This is me. And I know enough about myself to know that I can’t do ten pages on a dying preacher sanding the door of his chapel. So I cling to the self-serving belief that you will be more authentically you if I’m more authentically me.

Habitually, I do my work in daylight. These are my steady hours, the time to undertake the slow, patient business of accumulating words. But as the end draws near, evenings are better. Darkness is suited to endings.

We know what the ending needs to do: it should achieve some resolution or insight; answer some question implied in the journey of the central character; return us to the opening chord, but with it or us changed. But what actually is an ending? Which thresholds are truly final? Which are even real?

As we put the cylinders away, as we look forward to ascending from the basement, it feels as though we should consider the possibility, at least for a moment, that Notovitch was telling the truth; that on a certain day in 1887, he discovered a lost gospel in an Indian monastery.

We could go right now, if we wished, to Ladakh to check. Packing a bag with warm clothes and setting off immediately, we might reach Delhi tomorrow. We could be on the runway at Leh the day after, having overflown the astonishing Zanskar peaks and descended over Spituk Monastery on our approach to the city. Peering down from the aircraft window, we’re low enough to see monks in yellow robes and masks performing sacred dances in its central courtyard.

Such a sudden arrival at high altitude is, of course, foolhardy. The Bakula Rinpoche airport is two miles above sea level. Your head spins as you take your luggage off the carousel.