> With all due respect, many people like him do exist in the world, and perhaps you're not acquainted with people like him.

Fair enough.

> Basically, he believes in the truthfulness of large institutions, which really is why you and I believe the earth is round; that is, we haven't actually performed a bona fide experiment

I guess to a certain extent, but also knowing that I could perform such an experiment and come up with reproducible results. As well as the lack of any credible alternative theory that holds up to any sort of scientific rigor.

> One fact that stands out to me is that we all use some amount of faith to accept that the earth is round, though perhaps not quite a leap's worth.

I would say that it's not really faith when its reproducible. For example, there is a small amount of faith that my brakes will slow down my car when approaching a corner, but I can test the brakes to know they should work, I can perform experiments with similar mechanisms to prove the basic physics, that all would have reproducible outcomes. So while there is a small amount of faith that some catastrophic failure won't happen, I would say its categorically different to believing things with almost no evidence. There is no reproducible experiment (at least that I know of) that you can even read about that proves the earth is flat.