Change.

You know when you're walking down the street, and you're pretty sure about how the world looks, how everything is working? And then something happens, unexpectedly, and-

Paradigm shift.

You're suddenly living in a different place, a whole new planet, almost...and you start floundering, struggling to adjust...suddenly, painfully aware of how little you actually know...wondering what behaviour is acceptable in THIS place, how you should be reacting, what you should be doing...and then, with time's unstoppable, inexorable flow, you adjust. What was unthinkable yesterday, is obvious today. Life goes on, inescapably...

We humans ARE a strange race, ain't we?