It’s too open ended to answer definitively. It depends on how one defines selfish behavior and thought. The underlying issue with human behavior isn’t selfishness but self desire and self preservation. Selfishness is just survival behavior amplified to an extreme, or survival behavior in environments that don’t require those measures to survive. So “selfishness” is rooted in sense of self, and is relative. Someone who gives all they own and dedicates every free moment to others could make the most selfless person any of us knows seem selfish by comparison. So we could become extinct, we could be disposable drones in a hive, yadda yadda. It’s like saying “imagine if all people were good.” What is good- and taken to a far enough extreme isn’t anything problematic? That’s to say nothing of the goal. All those people working together to hunt humans for sport, or destroy the earth for instance.
It sucks because our brains are wired to make us happy when we:
Eat foods with lots of kilojoules
Own a lot of currency or flashy items to impress other people and possibly get a mate
Many things have been accomplished because there was a race between people. Power, money, a sense of accomplishment, they all make one want to progress, so that they can be better than the others. I suppose it could've hapenned in that world too but very slowly or not at all.
I'm a simple girl. I just want food when I'm hungry, drink when I'm thirsty, something entertaining when I've nothing left to do, world domination, a daily shower, and my friends.
Most people don’t want a better life than others. Most people just want to live their life, and we all have different ideas what life should be. Even when we agree on a goal we may disagree between equally valid solutions to achieve it based on our personal ethics. Ants are a great example of what can be done when you unite the many for a common good. The thing is- I don’t want humans to live like ants. Diversity, freedom, and individuality complicate anything with more than one person involved. Humans work for a common good when that work gets us closer to our personal goals, doesn’t stand against our goals, or doesn’t take away from us achieving our goals. It would be nice if we could better find ways to achieve peoples goals that also allowed great works like this.
Eat foods with lots of kilojoules
Own a lot of currency or flashy items to impress other people and possibly get a mate
*shakes your hand*
If we can't win their hearts and minds, then gunpoint will have to do.