Music symbolized the harmony of human relationships in Dutch paintings of the 17th century. In affluent Dutch families, it was customary for a young woman to play the lute, the guitar, or the virginal (a keyboard instrument similar to a harpsichord) at family gatherings and for suitors who came to call. She could spend time with a young man, unsupervised, without concerns about impropriety, as long as one of them could be heard to play an instrument or sing a song. In the painting A Lady at the Virginal With a Gentleman, by the Dutch artist Johannes Vermeer (1632-1675), a young woman wearing a jacket of yellow satin is playing the virginal for a well-dressed young man. A hallmark of Vermeer’s work is his use of diffused light to throw colored shadows on the furnishings of a room, and the room in this painting is filled with refracted light. In the design of this composition, the angles of the roof beams, the patterns of diamonds and squares, and the placement of the table, chairs, and pitcher have been carefully planned. There is a tiny hole near the woman’s yellow sleeve where the painter pinned a string to the primed canvas to mark lines of perspective converging at this point. In the mirror on the wall above the virginal, a reflection of the artist’s easel can be glimpsed, a subtle sign that this scene has been staged to create a work of art. Dutch painters of the 17th century were students of the art and science of perception and were committed to representing the world around them as accurately as possible. Vermeer is known for designing spaces to create intriguing compositions and is thought to have applied scientific advances in optics and geometry to make his images more lifelike.