Vakkotaur

First, let's get this taken care of. A while ago I wrote, not all that well, about some of the events of a certain day a couple years ago. There are plenty of people affected by those events, but I do hope someday that while it may be remembered, that the date of September 11 is more just another day again.

Now, on to the state of the world. I do not mean the political state, nor the economic state, nor even the environmental state in the commonly used sense. I mean the very basic physical state.

When young, people are now taught that the world, well the thing we're standing on anyway, is a planet which moves around the sun and is roughly round. People are taught that people once thought otherwise but now we know better. But, for the most part, this is taught and said rather than demonstrated.

Suppose, for a moment, I said something jarring, like "The Earth is flat." How would you prove me wrong? Or better, what would you suggest I do to prove myself wrong? Now I don't happen to have a spacecraft handy to tool around in and check the shape from space. And I'd prefer not to rely on others at all, or at least as minimally as possible. This seems like it should be a really simple thing, it seems so fundamental. That is, until you start thinking about it and don't want to take what someone else says for granted. What could an average person of average (or even less than average) means do to prove to himself that Earth is not flat?

I asked someone this and got a reply asking if I'd seen a lunar eclipse. I have. I have seen several, in fact. And yes, the shadow on the moon is curved. That shows a curve in two dimensions does exist. It doesn't prove a sphere, not right off anyway, as it could be argued that it is the result of a disc.

No, I haven't gone flat-earth crackpot from reading Pratchett. This is more of a Feynman curiosity and desire to know something because I checked it it myself, rather than relying on any authority. That's the difference between believing and knowing. Wouldn't it be nice to know?