Kahn made his enthusiasm for the First Unitarian Church evident even before it received final approval from the building committee. As early as October 1960, in a lecture in California, he had chosen it to illustrate a pair of terms—"form" and "design"—that were becoming key tenets of his philosophy. He used these words to describe his conception of architecture—and in particular his design procedure—as the translation of the intangible into the real. It was at this time that Kahn mythologized the way the design of the church had evolved, composing an account (accompanied by the now-famous diagram) that, since its publication in April 1961, has been seen as the clearest illustration of his design approach.
