Bruno Munari is a bit too well-known in the United States for children’s books. He’s less well-known for the breadth of his work. He was an artist, a designer, a writer, a teacher, an industrial designer, a TV host, and a curator working in Italy for most of the 20th century.

Around 1962 Munari wrote, 
Today it’s become necessary to demolish the myth of the star artist who only produces masterpieces for a small group of ultra-intelligent people. It must be understood that as long as art stands aside from the problems of life it will only interest a very few people. Culture today is becoming a mass affair and the artist must step down from his pedestal and be pre­pared to make a sign for the butcher shop if he knows how to do it. The artist must cast off the last rags of romanticism and become active, well up in present day techniques, materials, and working methods. Without losing his innate aesthetic sense he must be able to respond with humility and competence to the demands his neighbors may make of him. The designer of today re-establishes the long lost contact between art and the public, between living people and art as a living thing.
This appeared in the Milan daily newspaper, Il Giorno, where Munari wrote a regular column on design. The excerpt I read was from an article titled “Design as Art.” But he wasn’t always so earnest. One was entirely visual and called “Trying to Find a Comfortable Position”:

Munari’s writing exists mostly in Italian, but “Design as Art” also became the title for a collection culled from his Il Giorno columns, translated into English, and published by Pelican in 1971. 
In addition to writing in the newspaper about design, Munari was known for his workshops in museums, on live television, and in more traditional education venues like, you know, schools. He wrote and illustrated a series of books around these workshops. Drawing a Tree is one. It’s a small book, modest even.