This concept of tracking changes to a time line, over time, introduces what you might think about as a two dimensional view of time itself. There is what I would refer to as observed time (the movement of time itself) and perceived time (what particular points in time look like given some point in observed time).
You can imagine a picture that looks like this:
Perceived Time ^ 9 | C.CA..AB. 8 | A.....AB. 7 | A.AB..... 6 | A.AB..... 5 | A........ +-----------> Observed Time 123456789
The horizontal access represents a view into time. Movement along the vertical access represents a movement in time and potential restatement of history.
It's a fascinating way of looking at time two dimensionally. I suppose that their could be additional dimensionality to this model as well. In two dimensions it can describe "what I think happened." With a third dimension, it could represent "what I think I thought happened." And so on.
I'm sure a deeper study of philosophy and mathematics could give me a stronger academic and theoretical background for this conversation, but in the meantime, I think that modeling a two dimensional perception of time lines is sufficient for most uses:
ID Attributes Effective_Date Expiration_Date Perception_Start_Date Perception_End_Date
And the round-up for today...
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