I think the point is that reality isn't a belief system. You can believe, even sincerely believe, any number of things but that doesn't have any bearing on whether they're real. Reality is real whether or not anyone believes in it, and does not require the belief of some primate like you or me on an insignificant rocky planet.
You can believe, sincerely, that gravity isn't real but when you jump off a cliff you'll find that it is real despite your belief. You can believe that the moon is made of fine, aged gouda but when you get there you'll find that it isn't. Belief is meaningless outside of thought experiments.
Now, I know you probably think science is also a belief system - I've heard that from creationists before. Truth is, nobody "believes" in science. Science is just taking the evidence we have and coming to the most logical conclusion based on the majority of evidence. As evidence is collected, the scientific consensus can refine or evolve - this is the "changing" nature of science you mentioned earlier, and this change is precisely what makes science real. As more evidence is uncovered, knowledge is refined.
Note that "belief" usually can not permit any change, and that is precisely why it is neither correct nor scientific. All we know is what the preponderance of evidence indicates - no belief involved.
