One could argue that time as classically understood, simply doesn't pay rent, and exhort us into stating that there might be universes that exist were time flows backwards and the likes.
The concept of classical time pays rent quite handsomely, all of modern physics is based on it. "Time flows backwards" still implies a flow of time, not timelessness.
Today's post, Timeless Identity was originally published on 03 June 2008. A summary (taken from the LW wiki):
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