Clayton M. Christensen

I helped start a ceramics company called CPS Technologies. We took it public in 1987 at $12 a share. Three months later, there was this horrible cliff: Black Monday. Fidelity had bought 15 percent of our stock, and their algorithm caused them to dump it all onto the market that day. We dropped from $12 to $2.

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.