The future is unknowable because it depends on people and because people reflect, have will, make mistakes, co-operate and change their minds and ways. The past turns into one of many possible futures through human agency. The way to understand what is happening in the world is not to draw trajectories on paper but to ask what people are thinking and doing in their own lives and collective endeavours.
I think is what most teams that think about ‘futures’ for a living do, however. The outputs of processes such as scenario planning explicitly create ‘many possible futures’ as navigational aids, not pre-plotted courses to be slavishly followed.