David Reuben

There may be some backward countries where the mass of the people are on a subsistence level and where, as an aftermath of wars or partial crop failures, the standard of living has to be drastically reduced, but this certainly is not the case in our prosperous nations.

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.