'An emperor over his slave, you said. There are rules even for that. But still, no one would choose to be a slave rather than an emperor. And the ulema have twisted the Quran with all their hadith, always twisting it towards those in power, until the message Mohammed laid out so clearly, straight from God, has been reversed, and good Muslim women are made like slaves again, or worse. Not cattle quite, but not like men, either. Wife to husband portrayed as slave to emperor, rather than feminine to masculine, power to power, equal to equal.'

By now her cheeks were flushed, he could see their colour even in the dusk's poor light. Her eyes were so pale they seemed like little pools of the twilit sky. When servants brought out torches her blush was enhanced, and now there was a glitter in her pale eyes, the torchfire dancing in those windows to her soul. There was a lot of anger in there, hot anger, but Bistami had never seen such beauty. He stared at her, trying to fix the moment in his memory, thinking, You will never forget this, never forget this!

After the silence had gone on a while, Bistami realized that if he did not say something, the conversation might come to an end.

'The sufis,' he said, I speak often of the direct approach to God. It is a matter of illumination; I have… I have experienced it myself, in a time of extremity. To the senses it is like being filled with light; for the soul it is the state of baraka, divine grace. And this is available to all equally.'

'But do the sufis mean women when they say "all"?'

He thought it over. Sufis were men, it was true. They formed brotherhoods, they travelled alone and stayed in ribat or zawiya, the lodges where there were no women, nor women's quarters; if they were married they were sufis, and their wives were wives of sufis.

'It depends where you are,' he temporized, 'and which sufi teacher you follow.'

She looked at him with a small smile, and he realized he had made a move without knowing he had done it, in this game to stay near her.

'But the sufi teacher could not be a woman,' she said.

'Well, no. They sometimes lead the prayers.'

'And a woman could never lead prayers.'

'Well,' Bistami said, shocked. 'I have never heard of such a thing happening.'

'Just as a man has never given birth.'

'Exactly.' Feeling relieved.

'But men cannot give birth,' she pointed out. 'While women could very easily lead prayers. Within the harem I lead them every day.'

Bistami didn't know what to say. He was still surprised at the idea.

'And mothers always instruct their children what to pray.'

'Yes, that's true.'

'The Arabs before Mohammed worshipped goddesses, you know.'

'Idols.'

'But the idea was there. Women are powers in the realm of the soul.' 'Yes.'

'And as above, so below. This is true in everything.'

And she stepped towards him, suddenly, and put her hand to his bare arm.

'Yes,' he said.

'We need scholars of the Quran to come north with us, to help us to clear the Quran of these webs obscuring it, and to teach us about illumination. Will you come with us? Will you do that?'

'Yes.'

Seven. The Caravan of Fools

Sultan Mawji Darya was almost as handsome and gracious as his wife, and just as interested in talking about his ideas, which often returned to the topic of 'the convivencia'. Ibn Ezra informed Bistami that this was the current enthusiasm among some of the young nobles of al Andalus: to re create the golden age of the Umayyad caliphate of the sixth century, when Muslim rulers had allowed the Christians and Jews among them to flourish, and all together had created the beautiful civilization that had been al Andalus before the inquisition and the plague.

As the caravan in its ragged glory rode out of Malaga, Ibn Ezra told Bistami more about this period, which Khaldun had treated only very briefly, and the scholars of Mecca and Cairo not at all. The Andalusi Jews in particular had flourished, translating a great many ancient Greek texts into Arabic, with commentaries of their own, and also making original investigations in medicine and astronomy. Andalusi Muslim scholars had then used what they learned of Greek logic, chiefly Aristotle, to defend all the tenets of Islam with the full force of reason, Ibn Sina and Ibn Rashd being the two most important of these. Ibn Ezra was full of praise for the work of these men. 'I hope to extend it in my own small way, God willing, with a particular application to nature and to the ruins of the past.'

They fell back into the rhythms of caravan, known to them all. Dawn: stoke the campfires, brew the coffee, feed the camels. Pack and load, get the camels moving. Their column stretched out more than a league with various groups falling behind, catching up, stopping, starting; mostly moving slowly along. Afternoon: into camp or caravanserai, though as they went farther north they seldom found anything but deserted ruins, and even the road was nearly gone, overgrown by fully mature trees, as thick trunked as barrels.

The beautiful land they crossed was stitched by mountain ridges, between which stood high, broad plateaux. Crossing them, Bistami felt they had travelled up into a higher space, where sunsets threw long shadows over a vast, dark, windy world. Once when a last shard of sunset light shot under dark lowering clouds, Bistami heard from somewhere in their camp a musician playing a Turkish oboe, carving in the air a long plaintive melody that wound on and on, the song of the dusky plateau's own voice or soul, it seemed. The Sultana stood at the edge of camp, listening with him, her fine head turned like a hawk's as she watched the sun descend. It dropped at the very speed of time itself. There was no need to speak in this singing world, so huge, so knotted; no human mind could ever comprehend it, even the music only touched the hem of it, and even that strand they failed to understand – they only felt it. The universal whole was beyond them.

And yet; and yet; sometimes, as at this moment, at dusk, in the wind, we catch, with a sixth sense we don't know we have, glimpses of that larger world – vast shapes of cosmic significance, a sense of everything holy to dimensions beyond sense or thought or even feeling this visible world of ours, lit from within, stuffed vibrant with reality.

The Sultana stirred. The stars were shining in the indigo sky. She went to one of the fires. She had chosen him as their qadi, Bistami realized, to give herself more room for her own ideas. A community like theirs needed a sufi teacher rather than a mere scholar.

Well, it would become clearer as it happened. Meanwhile, the Sultana; the sound of the oboe; this vast plateau. These things only happen once. The force of this sensation struck him just as strongly as the feel of alreadyness had in the ribat garden.

Just as the Andalusi plateaux stood high under the sun, its rivers were likewise deep in ravines, like the wadi of the Maghrib, but always running. The rivers were also long, and crossing them was no easy matter. The town of Saragossa had grown in the past because of its great stone bridge, which spanned one of the biggest of these rivers, called the Ebro. Now the town was still substantially abandoned, with only some road merchants and vendors and shepherds clustered around the bridge, in stone buildings that looked as if they had been built by the bridge itself, in its sleep. The rest of the town was gone, overgrown by pine trees and shrubbery.

But the bridge remained. It was made of dressed stones, big squarish blocks worn so smooth they appeared bevelled, though they eventually met in lines that would not admit a coin or even a fingernail. The foundations on each bank were squat massive stone towers, resting on bedrock, Ibn Ezra said. He studied them with great interest as the backed up caravan crossed it and set camp on the other side. Bistami looked at his drawing of it. 'Beautiful, isn't it? Like an equation. Seven semi-circular arches, with a big one in the middle, over the deep part of the stream. Every Roman bridge I've seen is very nicely fitted to the site. Almost always they use semi circular arches, which make for strength, although they don't cover much distance, so they needed a lot of them. And always ashlar, that's the squared stones. So they sit squarely on each other, and nothing ever moves them. There's nothing tricky about it. We could do it ourselves, if we took the time and trouble. The only real problem is protecting the foundations from floods. I've seen some done really well, with iron tipped piles driven into the river bottom. But if anything's going to go, it's the foundations. When they tried to do those quicker, with a big weight of rock, they dammed the water, and increased its force against what they put in.'