> In my experience, no one who talks about “it’s easy; you can measure x for yourself” on the internet has ever backed up their claims with proof that they themselves have made said measurement or performed said experiment. In terms of rigorous debate, they don't need to. If someone disputes a theory, hypothesis, observation, or anything else, the burden lies with them. If your argument is that the distance to the Moon is not 237,000 miles, you've got to tell us what the distance is and how you measured it. If you don't dispute it, there's nothing to talk about.