It's a weird phenomenon that's unique to HN. I understand that the idea is to elevate online discussion here, but many do it to such an absurd degree that anything anyone says always has someone asking for a source.

I sometimes wonder how these people would have survived at parties or social gatherings before the Internet when you couldn't just whip out your phone, spend 2 minutes not talking to anyone, click on the first Google search result, and then proclaiming "um acksually..."