Who said, "A poem should not mean/But be"?

Archibald Macleish (1892-1982) said, “A poem should not mean/But be” in Ars Poetica.

When was the FBI’s Ten Most Wanted List started? The FBI's Ten most wanted list was started in 1950. In 1970, the FBI unofficially increased the number to 16.
What figure of Greek mythology is crushed by fate in Jean Cocteau’s tragedy The Infernal Machine (1934)? Oedipus is crushed by fate in Jean Cocteau's tragedy The Infernal Machine.
When was English first spoken in England? English was not spoken in England until 449, when three Germanic tribes from Denmark, the Jutes, Angles, and Saxons, invaded Britain. The Angles, who settled along the east coast of north and central…
What is the time span of Samson Agonistes (1671)? The tragedy Samson Agonistes by John Milton, about Samson's battle of faith and destruction of the Philistine temple, spans one day.
How do you spell the name Swift gave to his race of rational horses in Gulliver’s Travels (1726)? The name Swift gave to his race of rational horses in Gulliver's Travels is spelt Houyhnhnms. Their subjects, a race of nasty human-like creatures, had an easier name: Yahoos.
Who or what was “Udolpho” in Ann Radcliffe’s Gothic novel The Mysteries of Udolpho (1794)? "Udolpho" in Ann Radcliffe's Gothic novel The Mysteries of Udolpho was the castle of the evil Montoni in the Italian Apennines, and site of many scary events.