Isolde exchanged a quick smiling glance with Luca. They both knew that Ishraq and Brother Peter would be quarrelling within a moment.

Ishraq looked at him quite blankly. ‘What is wrong with eating an apple?’

‘Because it does not mean an apple. The apple signifies knowledge.’

Luca winked at Isolde.

‘The woman wanted knowledge?’

‘Yes,’ Peter said, adopting his teacher’s voice. ‘But it was God’s will that the woman and her husband should be innocent of knowledge.’

Ishraq looked as if she did not need his instruction. ‘I would have thought an all-seeing God could have foreseen that a woman would want knowledge,’ she said. ‘Why should she not? Why should I not? Would any woman want to live in ignorance? Would any man? And what does it benefit God to have people so ignorant that they are like these poor peasants – believing that people call up storms and the devil takes the time and the trouble to make them unhappy?’

Brother Peter was almost too irritated to speak. He picked up his papers, bowed to the altar and turned away. ‘There is no point trying to explain such things to you,’ he said. ‘You are a heretic and a girl.’ It would have been impossible to say which he thought was worse.

‘The Lord Lucretili believed that a girl could study, without straining her nature,’ Ishraq insisted. ‘Women like Hypatia of Alexandria taught Plato to her students without illness. So when Lord Lucretili was in Spain he sent me to study at the university of Granada. Education is important to us heretics. There are many Arab women who are educated. We Moors believe that a woman can study as well as a man. We do not think that it is godly for a woman to be an ignorant fool.’

‘But he did not send his daughter, Isolde, to learn heretic knowledge? He took care to protect her,’ Brother Peter said pointedly.

‘I wish he had!’ Isolde interrupted.

‘The lessons were in Arabic or Spanish,’ Ishraq said. ‘Lady Isolde speaks neither. And besides, she was raised to be a Christian lady ruling her lands.’

‘But how would we ever find out?’ Luca asked, almost to himself, going down the aisle to the open doorway, and looking downhill to the harbour where the quietly moving sea with its ugly burden of wreckage, looked as if it had never raged inland. ‘How would we discover if the earth had moved and caused the wave? If it happened far out at sea, or even under the sea? If no one was there to see it happen? How could we ever discover the cause?’

Father Benito walked beside him. ‘You know, the people of the village tell a story of a great earthquake that threw down the harbour walls – all this was about a hundred years ago – and then there was a great wave that washed all the boats out to sea and destroyed all the houses two deep back from the harbour. The bell tower of my own church was thrown down when the ground shook. It was rebuilt; we have the stonemason’s costs still in the church records. That’s how I know it to be true.’