But how could you be alive and not have observed that the earth is curved? Why does a mountain, building or ship disappear over the horizon if the earth is not curved? That alone should be sufficient evidence to believe that the scientific consensus on this is likely to be true.
I have not observed directly that a human will die after 3 days without water but having experienced thirst & dehydration in limited amounts, I have no reason to doubt that is likely the case.
That's what I don't understand supposed "rational" flat earthers. It's fine and somewhat rational to be skeptical of authority but when the contrary idea takes enormous leaps of faith to consider, it seems weird to me to believe something for the sake of it.
>But how could you be alive and not have observed that the earth is curved?
I know someone who is almost 40 years old that has never left his hometown. He's a reasonable person who holds gainful employment, but from our conversations, he's never been in a skyscraper, flown on an airplane, taken a road trip into the mountains, or even hiked up a large hill, for that matter. He also lives in a land-locked city, so he's never seen the ocean. As such, he has never directly observed the earth to be curved. With all due respect, many people like him do exist in the world, and perhaps you're not acquainted with people like him.
However, he is not a flat-earther because he spends much time on the Internet reading about the way the world works outside his hometown. 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 (not just going in an airplane or up a mountain) to measure the curvature of the earth for ourselves, but we trust the results of those who have, and we also accept that certain technologies like GPS as it is currently implemented can only work if the earth is round (not just in satellite orbits but also the slight-but-critical relativistic shift from a geosynchronous satellite).
>when the contrary idea takes enormous leaps of faith to consider, it seems weird to me to believe something for the sake of it.
That's cool, but many people are capable of believing in something for the sake of it. 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.