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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Opening an umbrella indoors is said to result in 21 days of bad luck. Some traditions hold that it is only bad luck if the umbrella is placed over the head of someone while indoors.
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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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Some motorcycle enthusiasts hang a biker's bell from a portion of their bike to protect themselves from evil road spirits.
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Collect seven or nine different flowers on midsummer eve and place them under your pillow and it is said that you will dream of your future spouse. (Sweden)
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An acorn should be carried to bring luck and ensure a long life.
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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.
49
It's bad luck to leave a house through a different door than the one used to come into it.
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