For me it is the fact that our blood contains iron. I earlier used to believe the word stood for some ‘organic element’ since I couldn’t accept we had metal flowing through our supposed carbon-based bodies, till I realized that is where the taste and smell of blood comes from.
Because time and direction are different metrics? West is a metric that only means anything in relation to something else in a straight line. It’s a direction. West doesn’t stop being west if you go too far. It’s always west.