In 1958 he decided to incorporate cartoon images such as Donald Duck and Superman as subjects in his paintings after seeing an issue of Mad magazine in a Paris bookstore.
[4] Art critic John Yau wrote of Saul's work in The Brooklyn Rail: His orchestration of the intertwining, overlapping, cartoony figures could only have been done by someone who absorbed the all-over compositions of the Abstract Expressionists.
[5] In 1964 Saul returned to the United States and settled in the San Francisco Bay Area where he lived for eleven years.
In the 70s, Saul moved into interpretations of historical masterpieces such as Rembrandt’s Nightwatch and Picasso’s Guernica, and also what he thought of as American scene painting making use of cinematic illusionistic space.
[8] During this time his content diversified and his style focused on ever more glamorous treatment of “low” subjects, heavily influenced by 19th-century painting.
[9] Saul’s work has often been independent of specific art movements and thus he "has spent a lifetime avoiding easy critical definition".