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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Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
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According to an age old custom, carrying a dead shrew in your pocket wards off rheumatism!
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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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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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Placing keys on a table is considered unlucky. (Sweden)
3
In Asia, the digit 4 never appears in any Nokia handset model number, because 4 is considered unlucky in many parts of Southeast/East Asia.
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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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