Brad Sherman

It would be great some day to have astronauts in a rover on Mars. But just about anyone except an oil company executive would say its more important to have 50 million solar powered vehicles in the United States.

Circumcision is obligatory for Jewish-born males - it must be performed on the eighth day after birth and is only postponed in the case of threat to the life or health of the child. Muslim parents also circumcise their male children.

We live in a crazily youth-orientated world nowadays. It's a trickle-down thing. We see pictures of lithe, attractive celebrity couples such as Brad and Angelina or the Beckhams cavorting around, covered in tattoos, stomachs as flat as the singing in early 'X Factor' rounds.

The historical novelist has to consider what has actually happened, while the SF writer is dealing in possibilities, but they are both in the business of imagining a world unlike our own and yet connected to it.