Why do we cry tears?
You blink. Your eyes feel wet. Maybe you're watching a sad movie, or you just got smacked in the face with a soccer ball, or you're laughing so hard you can't breathe. Whatever the reason — here come the tears, rolling down your cheeks like tiny saltwater rivers. But why? Why does your body decide that water leaking out of your face is the right response to... well, basically everything?
First, the mechanical truth: your eyes are always wet. Right now, as you read this, a thin layer of tears coats your eyeballs like a microscopic swimming pool. Every time you blink — which you do about 15 times a minute without thinking — your eyelids spread this liquid across the surface, keeping everything slippery and clean. These are called basal tears, your eyes' 24/7 maintenance crew.
