On these scant three sheets of paper, Diego Rivera explores a wide range of ideas on the subject of art. This document is important because of the depth of Rivera’s ruminations on aesthetic emotions, color, form, texture, touch, feelings, and perception. He discusses the relationship between tactile and visual space while looking at a work of art, and how to handle time, space, and perspective in pictorial expression. Rivera explains how textures generate aesthetic feelings and, therefore, pleasure. He rejects the use of textures in mural painting since they reflect “a lack of expressive power,” but not in easel painting. Rivera ends by quoting an ancient proverb: “If you cannot create, teach; if you cannot teach, critique.”

This letter is one of several questionnaires to which Rivera responded, especially in the final years of his life when he kept up a very orderly correspondence. In June 1956, Diego Rivera (1886–1957) replied to questions he received from Ben Ireland, a student at Kansas State University. Ireland sent his questions to several internationally known artists, and found Rivera through the Guggenheim Museum in New York. Rivera kept copies of what he wrote and gradually assembled an archive of his thoughts. This letter, written toward the end of his life, was more than a comment on textures; it was an excuse to reflect on his work and his aesthetic ideas. This letter on the subject of textures is not well known, but it provides essential insights into Rivera’s aesthetic thinking.Rivera criticizes artists who add materials to their works without knowing their physical-chemical compositions or functions. This critique is quite probably directed at David Alfaro Siqueiros (1896–1974) who, in about 1956, was experimenting with new materials such as lacquer and pyroxylin in visual arts. The letter contains a major contradiction where the writer insists that art apprenticeships should take place in experimental laboratories. Here, and in other documents, mainly those written between 1954 and 1956, Rivera has developed a sort of aesthetic theory in which he reveals his grasp of how people see, and explains how artists generate feelings of pleasure by creating works of art in which form and color are harmoniously combined, and by understanding the materials they use and the duration of aesthetic feelings. In the latter case, Rivera foreshadows ephemeral art and brief interventions in his claim that, though a work of art may last barely an instant, "It would be justified by those fleeting moments of beauty."