I'm pretty sure every vaccine goes through clinical trials to prove both safety and efficacy. The mere act of doing that debunks anti-vaxxers just as the mere act of publishing history about the Holocaust debunks Holocaust deniers. In that sense, anti-vaxxers get all the serious discussions they could ever realistically want.

Or hey--maybe they don't. Maybe there are some procedural mistakes going on and those clinical trials don't reliably replicate or something. But we all know vaccines still work. What should we do--try and fix our clinical trials, or just get those annoying anti-vaxxers to shut up? I say we improve the clinical trials.

Let's talk about another kooky idea: that OJ Simpson didn't actually murder his ex-wife and her friend, and that the LAPD planted all of the evidence because they are so racist that they decided to irrationally hate one of America's most beloved actors and professional athletes. You know what immediately happened after a jury of twelve people in Southern California seemed to actually buy this ridiculous conspiracy theory? By and large, the consequence was that American law enforcement radically improved their handling of evidence. It turns out that sometimes, even if you listen to people who are wrong and believe things that are completely crazy, you go out of your way to improve your own epistemic hygiene just to debunk them.

The thing is, this is a very hard subject to discuss without actually saying some of the possibly-true heresies that are being suppressed, because then the discussion just becomes a discussion of the alleged heresy. You can point out anti-vaxxers and I can agree that anti-vaxxers are wrong and that actual harm results from people believing anti-vaxxer arguments, but if I countered by suggesting a heretical belief that I believe to be true and to be wrongfully suppressed, I've put myself in a bad position personally and completely changed the subject.

So let's use the same historical example I've been using. Anti-vax is wrong, terrible pseudoscience. Lysenkoism was also wrong, terrible pseudoscience. If you have a civic tradition where not even pseudoscientists can be silenced, thrown into gulags, or executed, you run the risk that anti-vaxxers will convince people of pseudoscience and then people will die of measles because they listened to pseudoscientists. If you have a civic tradition that you should just silence people and throw them into gulags for promoting pseudoscience, you run the risk that Lysenko will become director of the Academy of Agricultural Sciences, falsely designate actual genetics as "pseudoscience", and promote pseudoscience while all of the legitimate scientists get silenced, thrown into gulags, or executed. To make matters worse, Lysenkoism won't work, you won't grow enough food, people will starve to death, and the only people who actually know how to fix it will be either dead, in gulags, or either silenced or intimidated from speaking up.

In other words, you're making the assumption that might literally makes right--that the truth will always be on the same side as power and that there is no way that kooks will ever hijack your anti-kook system. Are you really willing to take that risk? I'm not, which is why I'm willing to err on the side of celebrating heresy and contrarianism and allowing a free exchange of ideas. It's not a perfect system, but I think allowing the free exchange of ideas will, in aggregate and in the long run, systemically favor truthful claims over false claims far more than implicitly trusting anyone with the power to decide by force what's true and what's false.