i am hung up on the concept! aside from actors -- who might play a part, and then go back to being themselves.. I can image a case were somthing goes back to being what it was... (changes from one state, to an other, and then back to the first...)

who was the philosopher (Roman i think?) who pointed out you could not enter the same river twice.. because the water flowed, and while the banks of the river might seem the same, it was different water

as i typed, i realized atoms can go from one state to another and mercury, can go from quicksilver to cinnabar, and back to quicksilver.. ( a favorite of alchemist) but living things can't. as we move through cycles of time, we can't go back.. but if we were phoenixes.. this is similar to cycle.. but not a retrograde progression, a cycle..

in terms of social mores.. this is sometimes likened to a swing of pendulum.. moving from one extreme to the other, and slowly progressing to a middle point.

oh i am all a muddle...maybe you can find something... or everyone will have fun, pulliing my ideas like taffy, trying to make something of them..