I put my life on the line almost daily. In all likelyhood, you do, too! Literally on the line (and I know what that word means!). It's that yellow line down the middle of the road.
Think about it. Driving is so weird. Imagine a long, straight two-lane road. Now, if you remove the surroundings and that yellow line that separates the traffic coming and going, it would look like a really scary jousting match. In cars. At high speed. Near miss after near miss. It's crazy to pass other cars going in the opposite direction that closely!!!!
We trust these lines. Paint! We place our safety and our very lives in the "hands" a few kilderkins of yellow paint! Again, think of a curvy mountain road. Now, imagine driving on it without the lines - and without what the lines mean to us. Every curve is potential death. It's Russian Roulette. We're nuts.
Now, I know it's not just the line we trust. We trust every other person on the road to abide by The Line. These are total strangers - and worse. These are the people we disagree with on important matters, people who vote for the other side - for stupid reasons, people who bag our groceries wrong, people who would make fun of us for something (if we weren't passing each other at speed). I can't believe we can trust them with something as important as staying on their side of the road!! Don't you remember when you couldn't even trust your brother to stay on his side of the back seat?? And don't say that lives weren't at risk then, because you knew your dad would kill you both if you didn't knock off that bickering - if he could only reach far enough back (while driving at speed, spared from a head-on collision by a swath of yellow paint).
But even this life-saving miracle had a beginning. A center line was first used in the US in 1911 in Michigan! (Thank you, Google) It's amazing we survived without it! Considering, however, that cars only became common in the first few decades of the twentieth century, it wasn't really that long.
Next time you're on a two-lane road Just try it . Imagine it's a desert playa - no road, no lines. The competitors are instructed to start driving toward the car that will start two miles away, aiming to pass each other at about arm's length without slowing down. Would you do it at 60 mph? Would you do it at 40mph? Would you do it at all? Well, you do it every time you drive!!