My area of expertise is mathematics. A number of times I’ve explained to someone that the concept of infinite sets is a well defined one. There is a definition and it allows us to work with such sets. I provided the (from my perspective) simple definition and an explanation but to no avail. My point is that often times people outside of the area just don’t understand it. Personally I don’t care if someone doesn’t understand something but I do care if their misunderstanding becomes normative and endangers others.

Pre-internet nutjobs existed in all communities. Cranks and whatnot. This is nothing new. What is new is the scale at which such people can propagate their nonsense. The cost of convincing others your are right has drastically declined. The speed at which such stupidity can spread has greatly increased.

We have entered an era in which regulation of stupid, crackpot ideas may need to happen. If and when we do decide to crackdown on this it’s best to rely on expert opinion. This is of course just an opinion of mine.

I submit to you that the vast majority of what you believe is due to knowledge you gained form others and not from first principles as you put it.