This is absolutely trivial if you learned even the tiniest bit of special relativity, and yet hearing it yesterday (from an old lecture by Feynman) unexpectedly resonated in my mind.
It was like:
"If you remain sitting in a chair, you are maximising your movement into the future.
If you start running, you are slowing down your movement into the future, by diverting some of the same motion into one spatial dimension".
Powerful!
