“Pop music provides useful perspective on Plato’s association of poetry with madness. There was something dangerously irrational in poetry that worried the philosopher. It wasn’t the semantic content but the visceral power of the sound and rhythm. Poetry compellingly communicates feelings that lie beyond or beneath rational discourse. The physicality of poetic speech separates it from the conceptual language of philosophy”

Demander à la poésie du sentimentalisme…ce n'est pas ça. Des mots rayonnants, des mots de lumière…avec un rythme et une musique, voilà ce que c'est, la poésie.
Remark, June 22, 1863, reported in the Journal des Goncourts (Paris: Bibliothèque-Charpentier, 1888) vol. 2, p. 123, (ellipses in the original); Arnold Hauser (trans. Stanley Godman and Arnold Hauser) The Social History of Art (London: Routledge & Kegan Paul, 1951) vol. 2, p. 684.

"The Case for Xanthippe" in The Crane Bag (1969).
General sources

Introduction, sect. 2
La poétique de la rêverie (The Poetics of Reverie) (1960)

Introduction
Bards of the Bible, 1850

1920s
Source: 'Consistent Poetry Art', Schwitters' contribution to 'Magazine G', No. 3, 1924, ed. Hans Richter; as quoted in I is Style, ed. Siegfried Gohr & Gunda Luyken, (commissioned by Rudi Fuchs, director of the Stedelijk Museum Amsterdam), NAI Publishers, Rotterdam 2000, p. 151.

The Paris Review interview
Context: Goethe called his work one big confession, didn’t he? Looking at his work in the broadest sense, you could say the same of Shakespeare: a total self-examination and self-accusation, a total confession—very naked, I think, when you look into it. Maybe it’s the same with any writing that has real poetic life. Maybe all poetry, insofar as it moves us and connects with us, is a revealing of something that the writer doesn’t actually want to say but desperately needs to communicate, to be delivered of. Perhaps it’s the need to keep it hidden that makes it poetic—makes it poetry. The writer daren’t actually put it into words, so it leaks out obliquely, smuggled through analogies. We think we’re writing something to amuse, but we’re actually saying something we desperately need to share.

The Origin of Happenings (1976)
Variant: Concrete poetry is a fusion of visual art and poetry.