My job was to polish an old mirror in the height of a tower. Men and women would cross the mountain pass to me, weary and travel-worn. They would climb the thousand steps to see the mirror, which – and this was the only fact that I took pride in – was said to be the clearest there had ever been.

One day, three men arrived from the South wearing the plain clothes and spare accoutrements of the sages. I was hopeful, of course.

‘What do you seek?’ I asked them.

The shortest of them stepped forward and bowed, ‘We seek a mirror outside the dream’, he said.

‘Why do you seek it?’

The tall, thin one replied, tracing a rectangle with his forefingers, ‘When we dream of mirrors it is only the dream we see reflected.’

I had no choice but to offer them what they sought. I dropped the silk from a second mirror, every inch as flawless as the first glass and directly opposite to it. Within that labyrinth, which was yet a straight line, the mirrors continued to retreat endlessly, obscured by their perfection.

The men said nothing but descended the stairs and were lost to the deserts of history.