If you want the world on the same page, all of us pulling in the same direction, all of us heading for the same goal and getting along, then you want evidence to be the only authority and the source of all facts, so we all get closer to a universal truth, on the same--page so to speak.
The barrier to this is ideologies: baseless claims proffered as foundational truths. Religion and politics are full to over flowing with these, in fact, religion and conservatism are anthologies of these baseless ideologies.