I agree, allowed by who. Belief is free will of humans, you are free willed to believe in whatever you want. You can not say that Agnosticism is only rational approach, because it is for you and for me, but it is not for someone else. Don't try to prove something you believe in to, to other and try to put it in there head, because they will deny everything no matter how rational it is. That is why conflict happens in first place, people want to prove they are right and that there God is only one... Believe in what ever you want, and keep it to your self.