Portrait of Susanne Fourment by Peter Paul Rubens and the Golden Rectangle

Successive Golden Rectangles dividing a Golden Rectangle into squares (Portrait of Susanne Fourment by Peter Paul Rubens).

Peter Paul Rubens (1577 - 1640). Flemish painter, draughtsman and diplomat. He was the most versatile and influential Baroque artist of northern Europe in the 17th century. He is well-known for his Counter-Reformation altarpieces, portraits, landscapes, and history paintings of mythological and allegorical subjects.

Portrait of Susanne Fourment ('Le Chapeau de paille'). c.1625. Oil on panel. National Gallery, London, UK.
Rubens married Isabella Brant, the daughter of a leading Antwerp citizen and humanist Jan Brant. Susanna Fourment was related by marriage to Rubens' first wife, Isabella Brant. Later the widowed Rubens married Susanna's sister Helena Fourment.

A golden rectangle is a rectangle whose side lengths are in the golden ratio, one-to-phi, that is, approximately 1:1.618. A distinctive feature of this shape is that when a square section is removed, the remainder is another golden rectangle, that is, with the same proportions as the first. Square removal can be repeated infinitely, which leads to an approximation of the golden or Fibonacci spiral.
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