This Is Why You Cry
Tears of sadness are not chemically the same as onion tears
Why do we cry? Unclear vision and involuntary noises alerting would-be attackers was the last things our ancestors needed in those dangerous times. Why on Earth did we evolve that way? On the surface, it’s as confusing to us as it was to Arnold Schwarzenegger in Terminator 2.
“I know now why you cry. But it is something I can never do.” – The Terminator, to a tearful John Conner
After a full movie of working out a little bit about what it is to be human, the machine has worked out why we cry. It’s something unique to humans, as far as we can tell. Animals’ eyes water if they’re irritated, but they don’t cry with emotion. Not like us.
If they seem like they do, it’s because we can’t tell the difference just by looking. We can’t even tell the difference in people. I know that because as an actor, I’ve used eye irritants to cause wet eyes. On camera, it looks completely like I’m crying. It’s a common trick even amongst the best.
So our eyes release water to clear irritants. That’s a simple biological reason. But aside from that? When we’re sad? Happy? In trouble?
