Entertainment / Literature / Polygenesis: The theory that, if two similar stories, words, or images appear in two different geographic regions or languages, they are actually unrelated to each other. Each one arose independently. For an analogy, in both early Mayan architecture and in Egyptian architecture, pyramids are striking engineering features. However, since no contact took place between the two cultures, archeologists believe each group invented the design independently rather than adopting it from a single source (such as one group borrowing it from the other). Circumstances such as the lack of mortar, concrete, or flying buttresses ensured that both Mayans and Egyptians would come up with a wide-base structure to support any large or tall edifice--leading to pyramid designs by default. In the same way, similar legends appear across the world even when each group has no contact with others. Many cultures that master metallurgy create legends or myths about crippled smiths (witness Hephaestus or Vulcan in Greco-Roman myth, Weiland in Norse and Germanic legend, and Silverhand in Celtic myth). Cultures that do not master metal-smithing do not create crippled craftsmen-gods in their pantheons. This can be explained by the theory of polygenesis. Men who are crippled cannot join the hunters in gathering food or join the farmers in digging irrigation ditches, so they tend to stay in the village and work as craftsmen, developing skills that ultimately seem magical to the untrained without these years of experience. However, the archetype of the crippled craftsman/god does not appear in cultures without the technology of metal-working.
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