Lately I've been listening to lots discussions with conspiracy theorists and science-deniers, and I've noticed that, when their position is challenged with evidence, their responses generally fall into two broad classes:
1) They respond by modifying their original position to acommodate the new piece of evidence, which introduces additional assumptions/complexity. For example, when the existence of time zones is pointed out to flat-earthers, the typical response involves the Sun being a "spotlight" with a complex lampshade that reproduces the pattern of day and night we observe. When it is pointed out that a lampshade cannot reproduce the ring of perpetual sunlight needed in the Antarctic ring during the Southern-Hemisphere summer, they propose that the Sun is also shining through a dome made of refractive material of just the right shape, and so on and so on. For other conspiracy theories, this usually takes the form of adding more and more agents to the conspiracy.
Eventually the explanation they create is much more convoluted, and requires many more assumptions, than the widely-accepted explanation. Ordinarily, this is where Occam's Razor would come into play in advocating for the simpler explanation, but this doesn't usually seem to matter to people who advocate these kinds of ideas, which indicates that they deny that Occam's razor selects the best explanation. Without the constraints imposed by Occam's razor, they are free to make their theory as convoluted as necessary, and they have no reason to believe a simpler one. Given that discussions take place in a finite amount of time, and only a finite amount of evidence can be presented, their theory is always defensible by applying a finite number of complexity-increasing "patches."
2) They assert that the evidence is fake, and was either fabricated by authorities with an agenda, or was put there by some supernatural being to serve as a test for mankind (this latter assumption is quite common among young-Earth creationists). As the argument progresses, more and more of the features of the natural world are denied (fossils were put there as a test, video footage of the planes was manipulated, photos of space are all CGI, editors for science journals were paid off, etc.). In the extreme, this argument collapses into solipsism, basically arguing that the whole world is an illusion, so they can ignore all evidence, no matter how much is presented.
I have seen philosophical justifications of Occam's Razor and arguments against solipsism before, but the issue is that these responses are made with the understanding that the reader is aware of some philosophy in the first place. Typically, that assumption doesn't hold in these discussions, and so these arguments are typically not helpful. Therefore, the question is:
Is there a way to prevent the discussion from proceeding along either of these tracks, assuming that the other party has essentially no knowledge of philosophy?