Wikipedia - The heart has long been used as a symbol to refer to the spiritual, emotional, moral, and in the past also intellectual core of a human being. As the heart was once widely believed to be the seat of the human mind, the word heart continues to be used poetically to refer to the soul, and stylized depictions of hearts are used as prevalent symbols representing love. In European traditional art and folklore, the heart symbol is drawn in a stylized shape. This shape is typically coloured red, suggesting both blood and, in many cultures, passion and strong emotion. The hearts have constituted, since the 15th century, one of the red suits in most playing card decks. The shape is particularly associated with romantic love; it is often seen on St. Valentine's Day cards, candy boxes, and similar popular culture artefacts as a symbol of romantic love. What the traditional "heart shape" actually depicts is a matter of some controversy. It only vaguely resembles the human heart. The seed of the silphium plant, used in ancient times as an herbal contraceptive, has been suggested as the source of the heart symbol. The heart symbol could also be considered to depict features of the human female body, such as the female's buttocks, pubic mound, or spread vulva. The heart symbol could also be derived from the shape made by swans necks in a courting ritual, which resembles the heart shape.