On Koekohe Beach, just north of the small hamlet of Moeraki, there are a few dozen large, perfectly spherical boulders scattered along the tide line: the Moeraki Boulders. Tourists on the road between Christchurch and Dunedin stop for a while to stand around and on them and to take photographs. I drove up there today and took a few snaps myself. The boulders are unusual but not unique. There are several other sites in New Zealand where similar rocks occur, and, so I have read, they are found in other parts of the world. They have been fairly extensively examined and the process by which they were formed is no great mystery, although their uniformity and large size has meant that over the years legends have accreted around them, in much the same way that calcium and carbonates accreted around some core to form the boulders themselves, millions of years ago.
One of the legends is fairly modern. A few years ago an English amateur historian called Gavin Menzies visited New Zealand intent on proving his theory that in 1421 a large fleet of Chinese junks visited our country. And prove it he did! He had a whale of a time. From one end of the country to the other he found junks and Chinese forts, and lighhouses and goodness knows what else. Not a hillock nor a bump nor a hole in the ground; not a Maori pa site, nor a rock nor a burp from his magnetic resonancing machine passed his notice without being declared a Chinese ruin of some sort or other. And he went ballistic with joy when he arrived at Moeraki. He found not just one but eleven (count 'em! 11!) junks. Squarish bits of sandstone were obviously bits of the concrete lining of old chinese ships, and the boulders themselves were (obviously!) ballast stones.
I won't try and disprove Menzies' theory. It has, of course, been comprehensively debunked elsewhere, but I will note, in passing, two things: That Mr. Menzies is the only person ever to suggest that the Chinese lined their ships with concrete; and the ludicrousness of the idea of trying to use dozens of rock balls 2 metres in diameter as ballast in a small wooden ship. Of course, no matter how much evidence is produced Mr. Menzies won't change his mind: he's a believer. He's a fundamentalist. By 'fundamentalist' I mean that his theory doesn't originate in the world around him, it originates between his ears. In other words, rather than encountering the world and then theorising about what he discovers there, Menzies works the other way around. He begins with his theory and then goes into the world to seek evidence for it. Seek and you shall find. If you start with a strong idea, such as a Chinese fleet in 1421 or a CIA plot to blow up the twin towers or the creation of the world in 6 days, the screening out of all that inconvenient counter evidence comes pretty easily, and the proof is there for all to see.
But then again, in actual fact all of our theories originate between our ears - even the nice broad minded liberal theories of people like you and me. Just like the fundamentalists we see the world not as the world is but as we are. Perhaps the real danger is ignorance of this fact. When we forget that our world view is tentative, provisional and approximate, and fool ourselves into believing that the way we see the world is some sort of ultimate truth then we are well on the way to believing all sorts of plausible tosh about flying saucers or Sarah Palin's pregnancy or 15th Century Chinese admirals.