Today is #WorldMathsDay! In addition to being a prolific artist, Salvador Dalí was fascinated by mathematical theory. "The Swallow's Tail" is recognized as Dalí's last painting & is a curious meditation on the graphic patterns associated with René Thom's catastrophe theory, a mathematical field that examines dynamic systems like hurricanes or traffic patterns. Dalí once described Thom's theory of catastrophes as, "the most beautiful aesthetic theory in the world.” In this piece, Dalí incorporates the seven equilibrium surfaces as identified by Thom: fold, cusp, swallowtail, butterfly, hyperbolic umbilic, elliptic umbilic, and parabolic umbilic. Each line represents one of these surfaces and acts as a visual representation of Dalí's understanding of mathematical theory. Credit: Untitled (Swallow’s Tail and Cello), 1983 Collection of the Fundació Gala-Salvador Dalí, Figueres.