The Golden Rectangle and The Persistence of Memory (1931), Salvador Dali

Successive Golden Rectangles dividing a Golden Rectangle into squares (the Persistence of Memory by Salvador Dali).

The Persistence of Memory is the most famous painting by artist Salvador Dalí. The painting has also been popularly known as Soft Watches, Droopy Watches, The Persistence of Time, or Melting Clocks. It has been owned by the Museum of Modern Art (MoMA) in New York City since 1934. The well-known surrealistic piece introduced the image of the soft melting pocket watch. It epitomizes Dalí's theory of 'softness' and 'hardness', which was central to his thinking at the time.

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.

Fibonacci numbers (0,1,1,2,3,5,8,13,21,34...) are a sequence of numbers named after Leonardo of Pisa, known as Fibonacci. The first number of the sequence is 0, the second number is 1, and each subsequent number is equal to the sum of the previous two numbers of the sequence itself.