Anything

Paradigms are always shifting.  Life is change.  Even when isolated, impermanence is apparent.

Almost everything will be different at the end than it was at the start.  Sudden changes are just more obvious.  Eyes frame the world on a different timeline, incapable of placing points of arbitrary reality.

Sitting in the parking lot of the ER for hours inspires reflection.  A connection to your parents and their parents makes time seem irrelevant.  You have your time and that time will remain only as long as the electrical impulses in someone's mind remain.