"You should care because nobody else does"Sure. It's a decent enough reason. But it seems born from an overly cynical thesis.
How about a better reason? Care because you want to. Make a conscious effort to give every stranger you encounter the benefit of the doubt. Some will prove you wrong, naturally. But until they do, they're presumed innocent.
It's actually pretty remarkable how much of a difference this approach can make in your daily life. People on HN like to talk about "expanding their luck surface area," and other terms of that nature. Well, being genuinely interested in other people is one of the better ways to do it.
Our lives are stressful. Our patience is thin. Our guard is up. All of that seems to come with the territory of modern life. But resolving to push that crap down, and treat other people respectfully, takes an enormous amount of strength. And it's a mark of good character.
Have something you stand for in life. Have a code. Make being a good, friendly person part of that code. This isn't corny. This is strong. This is badass. James Bond lives by a code. Batman lives by a code. See if you can rise to the challenge, and do the same.