Atheism
Updated onThe beauty of love your neighbor as yourself is that it's self-justifying. If you want people to be kind to you, be kind to people.
So where does God come in? Herman Cohen said that Judaism discovered the idea of humanity in the stranger. It seems funny that humanity had to be discovered in the first place, but even the best ideas have to be invented. So maybe God was just a palatable delivery mechanism for the idea, back when it was new.
But it's been a while since Leviticus, and we don't need a godhead anymore to take this moral imperative seriously. And if we do, I think that's a bad sign. It means we only ever do the right thing because we're told to. But if we ever want to mature as a species, we need to adopt these moral principles as our own, and stand by them for their own sake.
If someone asks why they should be kind, what's the more convincing answer? Because God said so or because that's how you'd like to be treated?
We are citizens of the world, and therefore responsible for making it. You can't escape this responsibility, even if you choose to shirk. Your actions have consequences whether you believe that or not. You don't get to just decide you don't matter, because your actions affect other people, and therefore they always matter. I don't matter is an excuse to be ethically lazy.