When you speak of bad luck, it is said that one should always knock on wood. Also knocking when speaking of good luck apparently helps with having good luck. This is an old Celtic tradition related to belief of wood spirits.
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Pirates believed that piercing the ears with such precious metals as silver and gold improved one's eyesight.
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An acorn at the window will keep lightning out
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A single magpie is considered a sign of bad luck. A Guide to the Scientific Knowledge of Things Familiar recites an old proverb concerning the incidence of bad weather when magpies forage alone and a possible scientific explanation for this.
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Breaking a mirror is said to bring bad luck for 7 years. To "undo" this, take the shards of glass and bury them underneath the moonlight. In ancient times, the mirror was said to be a window to the viewer's soul. If that mirror were to break, it would
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It's bad luck to leave a house through a different door than the one used to come into it.
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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
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