Science fiction is hard to define because it is the literature of change and it changes while you are trying to define it.

While persistence offers no guarantees, it does give 'luck' a chance to operate.

Our reading can affect our imaginations in ways of which we are not consciously aware. It is quite common...to re-read something after a gap of many years and realize that it has been there all along, without any memory of where it was first encountered. But it may have been working away all the time.