text [Linear / cyclic]At the horizon one can see the sky and sea touch each other. But this never really happens. If someone tried to find the place where sea and sky meet, he would never succeed. Earth (sea) and sky are two non-intersecting spherical spaces, one inside of the other.
Is time linear? Or is it warped into an endless loop, similar to that of Eearth (sea) and sky?
In the same way sky and sea seem to be getting closer to each other, also the civilisation seems to be getting closer to a critical point, a climax or a final stage. But this process will probably never be completed. As one can never find the intersection of sky and sea, there may be no end of humankind, no destination, no future. All historical events people perceive as important, introducing a "new era", may be equivalent to waves on the sea surface: They rise, reach their climax and vanish.
Linearity gives people hope. It helps to have aims, to take in life as a unique game, to see a light at the end of the tunnel. What if the light is the rear one of a train going on a around-the-world circle line? One day when the spectator may think he's closer to the light then ever before, the engine will knock him down from the back...
In fact there may be no end, no start, no progress. Just waves on the sea surface.