Duration, time, same same...in that they are both anchored to the single universal percept of persistence. Time looks like relative motion. But relative motion in turn hinges on the deep conviction of persistence of objects, each (at any scale) continuing to "be" (whatever that means for an object!) what it "was".

This is a very convenient construct, just like a freeway is a convenient construct.

That doesn't make it "true", just "real".

Liebenscheiss