The stylised heart: how a shape became the symbol of love

Few signs are as recognisable as the stylised heart, with its two lobes and its point turned downwards. Yet its history is less straightforward than it seems: the shape we draw on cards today does not resemble the anatomical organ, and its link with love took shape slowly, through ancient philosophy, courtly poetry and medieval miniatures. Following this path means crossing two thousand years of ideas about where feeling resides in the human body.

The heart as the seat of the emotions

For many ancient thinkers the heart was the centre of inner life. Aristotle regarded it as the seat of sensation and thought, while the medical tradition associated with Galen gave a greater role to the brain, though it still left vital heat to the heart. In the Bible the heart is where moral decisions are made and where affection is born. This legacy made it natural for medieval poets to place love in the heart as well, understood as a wound, a fire or a gift to be offered to the beloved.

A shape of disputed origin

Several hypotheses have been put forward about the origin of the two-lobed design, none of them truly proven. One of the most frequently cited points to silphium, a plant of Cyrenaica much prized in antiquity and probably now extinct, whose fruit appears on some coins of Cyrene with a heart-like outline. Others think instead of the evolution of plant motifs, such as the ivy leaf, which is extremely common in Greek and Roman decoration. In these cases, however, the shape did not yet carry any romantic meaning.

The decisive step came in the Middle Ages. A miniature in the Roman de la poire, a thirteenth-century French poem, shows a lover handing his heart to his lady: the organ still looks rather like an upturned pear. During the fourteenth and fifteenth centuries the outline became more regular, with the point at the bottom and the notch at the top, until it settled into the form we know and began to appear on coats of arms, seals and decorations.

From playing cards to devotion

In the fifteenth century the heart entered an object destined for enormous circulation: playing cards. The French suits, which arose in that century, included hearts alongside spades, diamonds and clubs, and their printing helped make the design familiar throughout Europe. In the same period the heart appears on caskets, brooches and small objects given as gifts between betrothed couples.

A parallel strand is religious. Devotion to the Sacred Heart of Jesus, already present in medieval mysticism, spread widely after the visions of Margaret Mary Alacoque, a Visitation nun at Paray-le-Monial, in the second half of the seventeenth century. The heart surrounded by flames and thorns became a popular image, and its visual language intertwined with that of profane love, which borrowed its flame as a sign of passion.

The heart that decorates Valentine's Day today is therefore the result of a long process of layering: an ancient theory about the seat of the emotions, a medieval graphic invention and a diffusion helped along by printing and devotion. Each time we draw it we repeat, almost without knowing it, the gesture of the medieval lover who offered his lady the most intimate part of himself.