Sit incredibly still for the next 4.3 seconds. Try it. Do your dead-level-best to stay exactly the same as you are for the next week. Impossible. You can't even stay just as you are or even where you are for the next 0.0001 second.
Our bodies are finite physical beings. We exist within the confines of this physical space around us.
Try as we might to sit still, the reality is that our bodies are resting upon a planet that is in constant motion traveling through a solar system and galaxy that are in continual state of flux. We are not still.
We may persist in our foolish stubbornness trying to remain the same for months, days, or moments; but our flesh is dying, building, producing, and processing. It is changing...always.
We throw ourselves into so many things out of a vain sense of legacy, wishing to be remembered for some daring deed as a lofty legend of some sort. But as concerns this mortal coil there is an end. There can be no mortality without end.
I'll conclude this line of thought tommorrow.