(Psychological / emotional perspective)
In ordinary everyday life, symbols that have a long history become fixed in, and used by, our unconscious â often to represent other happier times or times when there has been more happening. Nailing an iron horseshoe to a door is said to repel evil spirits, ghosts and witches, iron being a folkloric specific against such things.
It will generally have this significance in dreams; each belief system has developed its own particular myths and stories.