Penn Jillette

I've had to change careers several times. Sometimes because my interests changed. Sometimes because all bridges have been burned beyond recognition, sometimes because I desperately needed money. And sometimes just because I hated everyone in my old career or they hated me.

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.