"They had no sins, Pearce," I reply. "They attended two sermons on a Sunday. They said their prayers morning and night, kneeling by the bed from which neither of them ever strayed. But look at me! I am boiling with lust, immoderate in my consumption of wine, irreverent in my speech and a self-deceiver. Why did the fire not consume me? Why is suffering so arbitrary? No, Pearce, it will not do. If God exists, He is surely cruel. He is the old and terrible God of Moses, the God of Abraham. But the most logical conclusion is that He does not exist at all."

It is interesting to note the ease with which I had let my faith fall from me. Any love I had hitherto felt for God, I had given to the King, who had reciprocated (not as God had done, by speaking through the mouths of fat bishops and having frequent recourse to long periods of enigmatic silence) by laughing at my jokes and giving me royal kisses far sweeter to me than any embrace I'd had from any woman. It was the absence of these tender expressions of friendship and affection that had plunged me into such despair and sent me scrabbling about in the darkness once more, in search of my lost Redeemer, however cruel He might turn out to be.

This search of mine, these glow-worm prayers I sent out into the starry sky above Meg Storey's roof, if they failed to bring God back to comfort me, did, after a few weeks, send me my old friend, Pearce, who arrived at Bidnold on a mule. Strapped to the mule's back, were Pearce's pitiful worldly possessions (referred to by me, rather wittily, I think, as his "burning coals", in reference to a mad Quaker at Westminster who had wandered about calling the fops to repentance with a dish of the said coals balanced on his head). What Pearce owned, in fact, was the following: three Bibles, one copy of his beloved Harvey's De Generatione Animalium, various other anatomical tracts, including works by Vesalius and da Vinci and Needham's Disquisitio Anatomica De Formato Foetu, some quill pens, a black coat and hat, two pairs of black breeches, some torn shirts and stockings, a box of rusty surgical instruments, a single pewter mug and plate and a china soup ladle made in Lancashire. This ladle was the only legacy of his mother, who had died in poverty to send Pearce to Cambridge. Sometimes, in the melancholy moods that so frequently afflict him, Pearce would hold the ladle close to his body and let his long fingers caress its cold surface, in the manner of a lute player plucking a living tune from its dead, hollowed wood.

I was glad, I will admit, to see Pearce. When Will Gates informed me that a man with a long neck and dressed in black was coming up the drive on a mule, I knew it could be none other than my old friend and former fellow-student and I ran out to greet him.

It was drizzling slightly and both Pearce and the mule appeared wet and muddy.

"We have come from the Fens," he announced in his voice of doom.

"From the Fens, Pearce?" I said. "What were you doing there?"

"I am a Fenlander now, Merivel," he said. "My work and life are there."

"I notice that you put them in that order, Pearce: work first, life second."

"Naturally. Except that the two are inseparable."

"Well, I do not work at all, except a little painting."

"Painting? How peculiar."

"You've left the Royal College, then?"

"Yes. I work only with the insane. Take the mule, will you, and see she's fed? We're both very weak."

Pearce then dismounted, staggered a pace or two and fell to his knees. I shouted for Will Gates, who came running like a bullet, and together he and I helped Pearce into the house. I asked the groom to rescue the "burning coals" quickly, before the mule died and rolled over on the soup ladle.

We put Pearce to bed in the least colourful of my rooms, the Olive Room, a north-facing bedchamber, in which I had left intact some dark panelling and had curtained the bed in a sombre green, only enlivened by a little crimson fringe. Here, after drinking some venison broth and enquiring whether his books could be sent up to him, he fell into a sleep that lasted thirty-seven hours. During most of this time, I stayed at his bedside, checking his pulse now and then, listening to his breathing, dozing a little and sipping claret and staring at his elongated grey face, which I found at once so irritating and yet so inexpressibly dear to me.

When he woke up at last, I was anxious to tell him of the despair into which I had fallen and to see whether he could suggest any remedy. But he had, it turned out, made the arduous journey on the mule from the Fens for one reason only: to reveal to me that he had found, in his work with the mad people of what he called the New Bedlam, located somewhere between Waterbeach and Whittlesea, a deep and profound sense of peace, and to try to persuade me to leave my life of "vanity and show" to join him in his labours.

"I sense," he said, staring at my freckled, ruddy and be-wigged visage, "that you're not at ease, Merivel. The light has gone out of your eyes. Luxury is suffocating your vital flame."

I looked down. Though I had a terrible urge to confess to Pearce, amid childlike tears, that it was not luxury that had robbed me of my happiness, but the King's abandonment of me, and that I was indeed a desperate man, though not at all for the reasons he surmised, I refrained from doing so, knowing that it would only lead Pearce into more flowery discussion of how the insane are the innocent of the earth, and how, only by succouring them "like little children" can we be saved.

"Thank you, Pearce, for your concern," I said, "but you are completely wrong. If my eyes appear a little lacklustre, it's merely because I have watched at your bedside for a great quantity of time with hardly any sleep. As to my vital flame, it is burning very brightly."

"I know you, Merivel. When you stood in my room in Caius and put your hand on that man's heart, then it was burning!"

"Indeed! And if you had seen me in the park the other day with my oil paints – "

"You hope to find salvation in art?"

"I'm not speaking necessarily of salvation…"

"But I am, Merivel. For is not death the supreme moment of mortal existence, the hour in which we reap what we have sown?"

"You choose to see it like that, Pearce."

"No. I do not choose. The Lord tells me it is so. And what are you sowing, Merivel, here in your palace?"

"It's merely a manor, Pearce."

"No! It's a palace! And full of iniquity, if these scarlet tassels are anything to go by."

"They're nothing to go by."

"Answer me, Merivel. What are you sowing?"

Again, I looked down. The agricultural metaphors with which the Bible is strewn have always struck me as simplistic and crude, but I particularly did not like Pearce's repeated emphasis on the word "sowing", for it somehow evoked in my mind my letter to the King, which had been intended as a seed in the forgetful Royal brain, but which had indubitably fallen upon stony ground.

I looked up at Pearce, white and gaunt on his white pillow.

"Colour," I said. "Colour and light. I am sowing these."

"What pagan, freakish piffle you do spout, Merivel!"

"No," I said. "Have a little faith, Pearce. Through colour and light, I hope to arrive at art. Through art, I hope to arrive at compassion. And through compassion, though the journey may be a deal more terrible than the one you've just undertaken – your mule is dead by the way – I hope to arrive at enlightenment."

"Enlightenment," said Pearce with a sniff, "is not enough."

"Perhaps. But sufficent to be going on with."

Before Pearce could comment upon this, I plucked his ladle off a walnut escritoire, where a servant had placed it, and handed it to him.

"Here is your ladle," I said. "Play upon it quietly, until you feel restored enough to venture downstairs, where I have something of great beauty to show you."