The problem, as I see it, is the way that science is taught in schools, particularly at the primary school level, which for many (likely most) people in any given community is the only science education they ever get.
See, people have this impression, based on that educational experience, that science is much the same as all the other subjects we study. But it is not. Science is fundamentally different, and most people are never exposed to that fact.
Worse, we use the word "science" in two distinct ways, and this only adds to the confusion. "Science" can mean "The methodology by which we find out about reality"; But it can also mean "The body of information generated by the scientific method"
Education (in the west, at least) started off as a religious activity, and in primary education, this history has an enduring footprint. When teaching children about Christianity, there is a primary reference, the Bible, which is supposedly unquestionable, and which contains the right answers. Even in non-Christian religions, there are fundamentals that are to be accepted without question; And behind it all is the pre-literacy understanding that writing is magic.
If something is written, then it is true. The answer is in the book.
If a teacher and his student are in dispute, they resolve the dispute by refering to the textbook. The book has the right answer. If the book agrees with you, you win the argument.
Science (the methodology) fundamentally rejects this. In science (the methodology), books are just the words of people who are not even present; No dispute can be resolved by direct reference to mere writings. The writings themselves must be tested against reality.
Science (the body of information) is just an attempt to save time and effort. When the methodology has been applied repeatedly to a given question, and has so far always given the same answer, we write the answer in a book and get kids to memorise it, not because it is The TruthTM, but because it would be impossible to get things done if every time we wanted to examine anything, we had to start by demonstrating (yet again) that matter comprises particles of such-and-such a mass, with such-and-such an electric charge, etc., etc.
When I want to know the speed of light in a vacuum, I look it up in a book. Not because the books are never wrong, but because I have decided to provisionally trust the existing science (the body of information), as a time saving shortcut. If I had any inkling of a doubt, I could, should, and would reject what is written, and go test for myself using science (the methodology) to find the speed of light in a vacuum.
Disputes in science (the methodology), regarding what is a part of science (the body of information) are resolved by reference to reality - we devise and conduct experiments to test hypotheses, and these experiments belong, not to a priestly class, nor to a teacher who has control of the textbook, nor to a Board of Education who decide which books are textbooks and which are not, but to anyone who wants to conduct them.
Science (the methodology), unlike any other educational discipline, is ruthlessly egalitarian. Anyone can overturn science (the body of work) by coming up with a test that anyone else can repeat, and which reliably demonstrates (a part of) that body of work to be false.
But (at primary school) we teach science (the body of work) the way we teach religion; And we don't teach the methodology part at all, or if we do, we treat it as though it were just another rule to be memorised and regurgitated without question.
Kids are left with the impression that science (the body of information) is just another set of beliefs. And as we see from the massive diversity of sects just within one major branch of one religion, this implies that anyone can just make up any old rubbish they like, and then set about collecting disciples, adherents, and evangelists to believe it and spread the word. The criteria for success are having as many adherents as possible; Having evangelical zeal, to accrue still more adherents to your position; And most importantly of all, having a book.
Science (the body of information) is taught this way in schools. So it's hardly surprising that so much pseudoscience arises amongst those with limited exposure to science as a methodology, rather than as a body of information.
This fundamental failure to grasp what science (the methodology) is, or how science (the body of information) came to be, and how it can be (and constantly is) changed as new observations are made and new experiments carried out, is at the root of the problem here.
We can talk about free will, eyes as sense organs, how light works, etc., etc., until the cows freeze over, and it won't change a thing - because peacegirl is not on the same page as the rest of us. Peacegirl doesn't understand that science differs in any important way from theology, and so is determined to win her argument on the basis of theological rhetoric. She has a new book, and wants it to replace, or supplement, the old book. Because she thinks that's how knowledge works.
She does not, and perhaps cannot, grasp that the science books we use are not books of power, but are mere aide-mémoires that tally the current state of the game.
Replacing Newton's Optiks, or Einstein's General Relativity, or Maxwell's Electromagnetic Equations, with a new book of wondrous claims is not only difficult; It is futile. No part of science (the methodology) is beholden to books of science (the body of information); Unlike in literally every other educational discipline*, in science the relationship is reversed.
The body of work derives from, and is entirely subservient to, the methodology. You can subvert a church by replacing its Bible with a new work (a Koran, or a Book of Mormon, or the scribblings of L. Ron Hubbard, or of Lessans, or of anyone). But you can only subvert science (the body of information) by following the scientific method - and if a change is shown by that method to be required, the science books are all rendered obsolete at a stroke. There are no sects or splinter groups - only people who have abandoned the scientific methodology, and thereby rendered themselves irrelevant.
The methodology is simple. Hypotheses, rigorously tested against repeatable and universally testable observations, and those shown to be false, discarded.
If you want to change science (the body of information) it is simple (but not easy): Just detail an observation that anyone else can make for themselves, which demonstrates that a part of that body of information is false.
Be aware that trust is not a part of science (the methodology). No scientist trusts anyone, particularly not himself.
The question is not "should we trust Newton, or should we trust Lessans?". The question is "Which of these two has given us the details needed to repeat his work, and surprise ourselves into agreeing with his answers, starting from a provisional assumption that his answers are bullshit?"
Newton has done that. You don't need to take his word for anything, and he doesn't ask you to; He has provided a detailed set of procedures for proving him wrong, and invites you to give it your best shot, either using his procedure, or coming up with your own. That, right there, is science.
* The very word 'discipline', meaning 'a field of study', carries the historical baggage of the idea that one learns by rote, from infallible books, whereby error arises only from incorrect reading or interpretation of the sacred text. Science ain't like that, but primary education usually acts as though it were.
It’s just really stupid and totally wrong, is all.