Because the word Time has two distinct, core meanings:-

1. Its the dimension of change. Its how we measure, calibrate and index change and change-events.
2. Its a collective term for the ‘flow’ of change. A non-specific set of change-events (like traffic is a non-specific set of vehicles).

And Time 1 could be said to measure Time 2.

Hence Time seems self-referencing. But isn’t really. Time 1 and Time 2 are different (abstract) nouns.

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