Some Christians tried to troll me once by saying that lack of belief is a belief system. Of course, they were busy and had to leave before I could reply to them. I have also heard people saying that no opinion is an opinion. If this were so, we wouldn't be able to call a journalist bat shit crazy if he reported that senator X gave his official opinion, and that is "no opinion". Just what kind of dumb shit is this?
If no belief were a belief, rocks would be believers. If no opinion were an opinion, trees would support/oppose animal rights. Just what kind of dumb shit is this? That fact that I look for evidence is not a belief. If it were, there would be no point to any rational inquiry. It simply won't be different from belief, imagination, and illusion.
Belief necessitates a believer. Without a believer, there is no belief. But rationally, evidence and truth are independent of the observer, independent of the self. There can be such a thing as Mary's beliefs or Adam's beliefs. There's no such thing as Mary's Conservation of energy. Conservation of energy is just true regardless of the observer.
Truth is not a theory. The Pythagoras theorem is true regardless of what you think. There's not a single right triangle in which it doesn't hold.