- To understand Vers libre, one must abandon all desire to find in it the even rhythm of metrical feet. One must allow the lines to flow as they will when read aloud by an intelligent reader.
- Polyphonic prose is a kind of free verse, except that it is still freer. Polyphonic makes full use of cadence, rime, alliteration, assonance.
- Can Grande's Castle (1921), preface.
- Life is a stream
On which we strew
Petal by petal the flower of our heart.
- "Petals," from Dome of Many-Coloured Glass (1912).
- Mr. Sandburg possesses a powerful imagination, which plays over and about his realistic themes and constantly ennobles them. ...strikes, and factories, and slaughter-houses, and railroad trains, all take on a lyric quality under his touch. ...When Carl Sandburg left college, he was no longer an unskilled labourer, working with his hands. He was a thinking man, with a brain charged with ideas and emotions, determined to do his part in bringing about the millennium. For Carl Sandburg... is a revolutionary; he must push the world to where he is convinced it ought to be. ...again and again, he deserts the seer's mountain peak for the demagogue's soap-box. ...Mr. Sandburg is like a man striving to batter down a jail with balls of brightly coloured glass. ...Whether constant preoccupation with disease is a healthy form of literature, whether it acts as a curative, is open to question. But we can surely say that to be curative the disease must be treated unsentimentally and truly. Mr. Sandburg has aimed at doing this, has striven hard to do it. For this, one honours him above his fellows. For this, and the spirit of beauty which pervades his work.