Out of all the book's trenchant dissections of all sorts of pseudoscience, my favorite is the bit on hollow earth theories, including Cyrus Reed Teed's unbelievable notion that we live inside a sphere.
The entire cosmos, Teed argued, is like an egg. We live on the inner surface of the shell, and inside the hollow are the sun, moon, stars, planets, and comets. What is outside? Absolutely nothing! The inside is all there is. You can't see across it because the atmosphere is too dense....One of the Gardner's key insights, in his analysis of crankish patterns of behavior, was to point out the crank's fondness for language games.
Like most psuedo-scientists, who wish to impress the reader with their vast scientific knowledge, Teed has a tendency to let his words carry him into obscurities sometimes hard to follow. Planets, for example, are "spheres of substance aggregated through the impact of afferent and efferent fluxions of essence...." And comets are nothing less than "composed of cruosic 'force,' caused by condensation of substance through the dissipation of the coloric substance at the opening of the electro-magnetic circuits, which closes the conduits of solar and lunar 'energy.'"It seems hard to believe that at one point Teed--who began calling himself "Koresh"--had roughly 4,000 followers. But then, one skim through Fads and Fallacies proves that it's not so hard to believe after all. It takes the Martin Gardners of the world to puncture our propensity to be drawn to the cruosic force of the absurd.