The other day I had coffee with a foreign friend who bore the fizzled hair and drooping face of long years of English teaching in Japan. It looked like the blood had been sucked from his skin and bicycle-pumped into his eyeballs.

"Last night," he wheezed, "I dreamt I was visited by the ghost of Noam Chomsky. It was so lifelike I was horrified."

"Are you sure it was a dream? Perhaps it was real."