Christmas tree – on the basis of the “Tribar”. Homage to Oscar Reuterswärd and Roger Penrose. Most probably the best-known and “simplest” impossible object is the “tribar”.
It has been used so often in the visual arts, design, advertising, and even in fields of psychology, has become such a familiar symbol over the course of the 20th century, that by now it almost does not even enter our minds to inquire into its origin. Scholars generally refer to the unusual triangle as the Penrose Triangle, because it was the later celebrated mathematician Roger Penrose who published it first. In 1956, still a student, Penrose was introduced to the works of Escher at a show in Amsterdam, and under this influence, he began to draw “impossibilities”, and to dissect paradoxes from a mathematical angle. Penrose published the drawing of his triangle in the February 1958 issue of the British Journal of Psychology. Escher made his lithograph entitled Waterfall on the basis of the drawing. Penrose could not have known – moreover, at the time, nor could Escher, that a young man living in Sweden, Oscar Reuterswärd, who had engaged with impossible objects for quite some time; in fact, he had already invented and drawn the “tribar” decades previous. A quotation from Reutersvärd’s letter to Bruno Ernst: “In my Latin class (in 1934), I drew a few versions in the margins of my textbook. I tried to draw 4,5,6,7- and 8-pointed stars as precisely as possible. One day I drew a 6-pointed star, then joined cubes to its sides. I got a surprisingly interesting form. Then I added another 3 cubes, so that I could complete the figure as a triangle. Immediately I realised that what I had before me was a paradox.”