If you don't fight against what's wrong in the world, don't expect everything to be right on your little world. 

And if you don't make the effort to improve yourself, don't expect the world to be a better place. 

All you do or don't has effects, even if you can't see it. 

If everyone focused in improving things that need to be improved in the world, as much as they focus in so many other individualistic things like vices and other pernicious activities, we would all live in a much better world.