A good paradox has the viewer confused, but the best paradoxes lead the viewer to try to understand what is happening. One of my favorites is the hydrostatic paradox, in which a short and slender column of water supports a relatively enormous weight. Figure 1 shows this paradox in action. In the picture a student weighing 60 pounds stands on a platform placed atop a flat water-filled rubber hot-water bottle. Connected to the bottle is a slender upright glass tube, also filled with water. A column of water only four or so feet high supports the student.

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