What's a Collective Belief?

What's something that requires a collective belief to be real? One example, i think, is rights. But there is no tangible thing that you can identify as a right. There are other things though, and i used the word before, matter, as in mattering,. Our loves, our principles by which we live, our relationships. The significance of the relationships is not just the two individual people, but this thing that binds them. And it's there, but it is not accessible to the senses. It's something that we comprehend. And it is something that, it is not a matter of believing if it's really there. So obviously you're not saying that if enough people believe