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 keys on a table is considered unlucky. (Sweden)
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Before traveling a person should, apparently, sit on their luggage. (Russian)
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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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The superstitious symbolism of a black cat crossing one's path is dependent upon culture: some cultures consider this a sign of impending bad luck, while some cultures consider this a sign of impending good luck.
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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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If you catch a falling leaf on the first day of autumn you will not catch a cold all winter.
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In some parts of England, rum is used to wash a baby's head for good luck.
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