What shape is your heart?
The human heart is a fist-sized muscle with a rounded bottom, smooth sides, and a thick arch of blood vessels at the top. So how did it come to be represented around the world by the pointy-bottomed, smooth-sided, cleft-topped icon drawn by doodlers, artists, and greeting card makers?
No one really knows. But neurosurgeon turned publishing executive Pierre Vinken has some ideas. In a fascinating little book, The Shape of the Heart, he traces the evolution of the heart's image.