A few years ago, I had a business interview and, even though I didn’t get a job offer, my interviewer gifted me a horseshoe—a hopeful parting gift to ease the sting of rejection. Since then, that horseshoe has been displayed in my home with the open side up, like a letter U, to collect good luck and keep out evil. Horseshoe legend began in Ireland in the 10th century when St. Dunstan, a blacksmith, outsmarted the devil by making him promise never to enter any place with a horseshoe above the door. Even sailors would nail a horseshoe to their ship for protection. The construction of a horseshoe is also lucky. Made out of iron, which can endure fire, and featuring seven nails—a lucky number. And let’s not forget, horses also enjoy the benefits of well-mounted horseshoes.