Robert Indiana kept a series of illustrated journals during the late 1950s and 1960s, in which he discusses the development of his work as well as his daily life on Coenties Slip.

In his journal entry for January 22, 1962, Indiana recounts being told over breakfast of a dinner the previous Saturday in which the sculptor David Smith had asked "who [the] hell [this] Indiana guy is," because Smith "considers me black and himself red." Indiana notes that "(Cuba or no Cuba). He likes Castro." 

Indiana then records going home to prepare for a studio visit by Mr. Lake, who was with the Kootz Gallery, but would not be visiting in an official capacity. He notes that as soon as he came in Lake said that his work was definitely not for Kootz, and began pondering what gallery he would be best for: "As everyone else thinks, he hit on Castelli first." 

Indiana writes that he applied himself to the second "EAT," and includes a sketch of the Eat panel from The Green Diamond Eat/The Red Diamond Die. To the right of the sketch he records using cadmium red light paint, and that the panel measures 60 x 60 inches (square). Below he details that he is now not certain about the field of this "EAT, with his first thought having been to "make it blue as if it were [the] sky . . . but it is very great now, and possibly [that] would lessen its impact."