A Universal Matter of Luck
Found in every age and culture, the horseshoe is one of the most common superstitious symbols. The roots of this belief date back to old times when the “U” shape was believed to hold in abundance, the holiness of iron, and to Ancient Rome, where the crescent shape symbolized the goddess of fertility. According to a Christian legend, an ironsmith chained the devil through trickery and released him only on the condition that he would not enter homes with a horse shoe on the front door. Horse shoes are hung upside down on doorways in order to keep the good fortune in a home.
It is a Matter of… Perhaps our ancestors would hang up old and unusable horse shoes on the doors in order to recycle them, and hope that they would bring good luck. Looking at today’s increasingly rare use of horses and horse shoes, it seems likely that the chance of a horse shoe bringing good luck has increased. Or, you could just use the modern-day equivalent, old car tires, to replace the horse shoe.