Superstitions have a way of making their way through thousands of years, one generation after another. In many, if not most cases, the basis for the superstition is lost to history even though the rituals persists through the ages.¹ Here we provide  many of the popular superstitions in western culture. 

Friday the 13th 

The Bible is often considered a book of numbers. In the Bible the numbers 7, 12 and 40 appear throughout the Old and New Testaments. The number 12 is considered a lucky number. As a result, the number which follows 12 was thought to be evil. Known scientifically as "Tridecaphobia," fear of the number 13 is probably the most common of all superstitions. Buildings avoid numbering the 13th floor. Airplanes avoid the 13th aisle. And most common of all, Friday the 13th is considered a bad luck day. Psychologists believe that Friday the 13th will become a day of bad luck if people focus on the day because people will create their own bad luck by paying attention to the superstition.²

Black Cats 

A black and white cat crossing your path means good luck. A black cat crossing your path will cause you bad luck before your journey is over. If this occurs you can take 12 steps backwards toward off the bad luck. If a black cat walks toward you it brings good luck. If it walks away, bad luck. A cat cleaning its face in front of the door is a sign of company. 

A cat draws lightning. 

A cat eating grass is a sign of bad luck. 

In ancient Egypt the cat was considered sacred and to kill one was sacrilege. It is believed that the folklore surrounding the black cat began in the Middle Ages when it was associated with witches. It is likely that a black cat was the pet of some women accused of being a witch. Rumors began that the cat was able to change shape and help the witch cast spells. Since then, black cats have been associated with luck, both good and bad. 

Knocking on Wood 

Knocking on wood is done to prevent bad luck. This comes from the ancient Celtics who worshipped the tree as the foremost worldly representation of the Divine. The power of a tree was used for support prior to battle and Druid priests performed all of their rituals and incantations within a sacred forest. The trees consumed all evil demons back into the ground. 

The ancient Celtic people of Europe worshipped the tree as the foremost earthly representation of the gods. If bad fortune visited, or if a battle was about to be fought, the power of a tree was invariably brought into force. The Druid priest performed all of his rituals and incantations within the sacred arbors. The trees consumed all evil demons back into the ground. 

Knocking on wood is noted for warding off punishment for bragging. People once thought that evil spirits would become jealous if good fortune was pointed out to them, and would relieve the bragger of that good fortune. Evil spirits were frightened away by the noise of knocking on wood three times, and would not  hear of  the good fortune. 

Walking under a Ladder 

Bad luck coming to a person who walks under a ladder is a superstition that has a couple of possible origins. Some believe it originates with the early Christian belief that a leaning ladder formed a triangle with the wall and ground. People must never violate the Holy Trinity by walking through a triangle. Others believe that it dates back to Medieval Europe and the attacks upon castles. When invading a castle with its draw bridge up, one of the means invading armies used was to place ladder on the walls and send troop up the ladders to fight their way into the castle.³One of the defenses for this invasion was to pour boiling oil or tar down the sides of the castle wall to repel the invaders. Those unfortunate souls that had to hold the ladders in place often received a deadly bath. It quickly became apparent that one had to hold the ladder from the front and that it was extremely bad luck to hold it from under the ladder. 

Today it is often still bad luck to walk under a ladder because of paint and other objects that might fall from above. 

Broken Mirrors 

Breaking a mirror brings bad luck for seven years. This dates back to times when it was believed our reflection was a representation of our souls. By damaging the reflection is damaging the soul. If we manage to break a mirror, there are remedies that will reverse the fortune of the damaged soul. We can take the broken pieces and wash them in a south-running river, therefore washing away the bad luck. Or we can bury them in the earth to neutralize the potential evil. But at least take the broken mirror out of the house and do not gaze into it. In vampire legends a vampire cannot see his reflection in a mirror because they possess no soul. In addition, bedroom mirrors should be covered before one retires for the night so their soul will not get caught in the mirror. Finally, in the home of the recently deceased the mirrors should be covered so the soul will not be hindered on its way to heaven. 

Kissing under the Mistletoe 

Mistletoe is actually a parasitic plant that lives off of a host, another tree that it can embed its root in, hardly a sensual connotation. However; the Celtic Druids, who worshipped trees conducted many of their ceremonies in the woods under the shade of trees, many of which had mistletoe plants attached.⁴It was under the trees that weddings took place and the bride kissed by all attendees. This gradually translated into women being kissed under the tree and eventually became the superstition that we know today; namely that a women standing under a mistletoe cannot refuse the kiss of a man. 

Lucky Rabbit's Foot 

Keeping a rabbit's foot near one is considered a method for bringing good luck. Like many superstitions, this one dates to the Middle Ages and witches. It was believed that a witch could transform herself into a hare (not a rabbit) to disguise herself when being pursued. While in the form of a hare they would suck the milk from nursing mothers. Carrying a hare's foot around warned the witches that they would meet a similar fate should they try such an act.⁵Of course, a lucky rabbit's  foot is not very lucky for the rabbit.

Lucky Horse Shoe 

Horseshoes are a traditional sign of good luck. Most believe this comes from the  fact that the horseshoe is shaped like the crescent moon, time of prosperity and good fortune. One legend says that the Devil called on St. Dunstan, who was skilled in shoeing horses. St. Dunstan recognized the Devil and fastened him to a wall. He then set to work with such roughness that the Devil roared for mercy. St. Dunstan turned the Devil loose after making him promise never to enter a home on which a horseshoe was fixed. Witches fear horses, so they are also turned away by a door with a horseshoe mounted on it. The big issue regarding horseshoes is whether they should be hung points up or  points down. The original superstition was that the horseshoe is points up to keep the luck from pouring out. Despite this view most buildings with horseshoes in their sign hang them the opposite way. The Horseshoe Casino in Las Vegas hangs it with the arc on top. (They may be hoping their customers luck runs out but this is usually not something you advertise in your sign). 

 

Finger rings made of horseshoe nails are said to ward off bad luck. Rubbing two horseshoes together is said to bring good luck. 

Four-Leaf Clover 

When Adam and Eve were expelled from the Garden of Eden, Eve took a four-leafed clover to remind her of their happy life there. Finding a four-leafed clover is now an omenof good luck. 

A poem by Higginson, titled "Four-LeafedClover" reads: 

The first to believe in the luck of the four-leafed clover were the Druids who were sure that possessing one would allow them to see evil spirits that they could then avoid. 

For the original text, pleas visit Superstitons,Omens, Myths, Mysteries, Talismans, Rituals and Urbans Lengends.