“A poem should not mean
But be.”
"Ars Poetica", Collected Poems, 1917-1982 http://books.google.com/books?id=KI0ESFOvi5QC&q=%22A+poem+should+not+mean+But+be%22&pg=PA107#v=onepage (1985)
Archibald MacLeish est un poète, dramaturge, essayiste et professeur d'université américain qui a également été bibliothécaire de la Bibliothèque du Congrès des États-Unis de 1939 à 1944. Il a fait partie du premier Conseil de chanceliers de l'Academy of American Poets. Il fut également membre de l'American Academy of Arts and Letters dès 1933. Wikipedia

“A poem should not mean
But be.”
"Ars Poetica", Collected Poems, 1917-1982 http://books.google.com/books?id=KI0ESFOvi5QC&q=%22A+poem+should+not+mean+But+be%22&pg=PA107#v=onepage (1985)
"The American Cause", address delivered at Faneuil Hall, Boston, Massachusetts (November 20, 1940); reported in MacLeish, A Time to Act; Selected Addresses (1943), p. 115
Return from the Excursion, Riders on Earth (1978)
“What is more important in a library than anything else — is the fact that it exists.”
"The Premise Of Meaning" in American Scholar (5 June 1972)
Now Let Us Address the Main Question: Bicentennial of What?, New York Times (3 July 1976)
"In Praise of Dissent", New York Times (16 December 1956)
As quoted in Richard Nixon's First Inaugural Address (20 January 1969)
Attributed
“If God is God, he is not good. If God is good, he is not God.”
Dialogue from MacLeish's play J.B. https://en.wikipedia.org/wiki/J.B._(play), an adaptation of the Bible's Book of Job, also quoted in The God Problem: How a Godless Cosmos Creates (2012) by Howard Bloom