See here for a longer interview which includes the screenwriter Alex Garland. Highly recommended! Also available at iTunes.
The dystopian science fiction setting is primarily a device for Ishiguro to confront the Fundamental Question of mortality.
Have our lives been any different from the lives of the people we save? We all complete. Maybe none of us understand what we've lived through. Or feel we've had enough time.
Here is my daughter's first encounter with the Fundamental Question.
Last night at dinner my 4 year old daughter asked me about death.
"Do all princesses grow old?" she asked.
"But I don't want to die!" she said, knowing, it seems, full well what that meant.
"We might go on to something else after we die," I offered.
"Oh." She thought about that for a while.
My son doesn't seem concerned about any of this, although he does occasionally ask me what the biggest number is. (He also wants to know about the biggest dinosaur and the fastest rocket.) I usually ask him to name the largest number he can think of, and then point out that I can always add one to that to get an even larger number.
When I was a kid I spent a lot of nights pondering life and death and infinity. I still do.