"Principles of Vision insists on the artist assuring himself that he distinctly sees what he attempts to represent. What he sees, and how he represents it, depend on other principles. To make even this principle of Vision thoroughly intelligible in its application to all forms of Literature and Art, it must be considered in connection with the two other principles sincerity and beauty, which are involved in all successful works."
January 1, 1970
https://en.wikiquote.org/wiki/Intelligibility