(@jamesbritt I accidentally hit the downmod arrow (I meant to upmod) . Could someone up mod this please? Thanks in advance.)<p>"Sure, you're entitled to believe what you want, but if you make it public then expect others to ask questions, and absent any evidence or a good argument, to scoff."<p>The "make it public" is key. Sure we are not having a debate, but then no one is asking for results from double blind randomized trials either.<p>For me to say something (and expect people to accept the truth of what you say -  I could be honestly mistaken for example), asking for data is a <i>good</i> thing. It forces me to reflect on why I say what I say  and if the "why" is weak, then maybe I need to rethink.<p>".yet my opinion isn't valid because I don't have research data to back it up?"<p>Your opinion is valid <i>as an opinion</i>. it isn't valid enough to be accepted by other people without data/logic/whatever backing it up.<p>It might help if any such request, even if abrasively phrased, could be reinterpreted as"What makes you think so?".