If we are in a situation where we are unable to collect the data in the first place that's mischaracterising my point. I didn't say anything about having no d

If we are in a situation where we are unable to collect the data in the first place that's mischaracterising my point. I didn't say anything about having no data. I talked about when the data you're able to get is unrepresentative. from what place did these putatively superior data or opinions come from? Because they clearly aren't coming from data. i think that's just playing word games with "data". We're talking about data concerning the problem at hand. Theories may come from data, but they don't come from data you obtain about the problem at hand. And knowledge can come from experience, which again is a form of data, but clearly not the sort the person was talking about. You can reason based on knowledge and principles. Sure, it'd be better if you had good data, but when you can't have that sometimes the best you can do is to reason based on knowledge/experience/theoretical ideas.