You cannot lecture on really pure poetry any more than you can talk about the ingredients of pure water-it is adulterated, methylated, sanded poetry that makes the best lectures.
Even a vortex is a vortex in something. You can't have a whirlpool without water; and you can't have a vortex without gas, or molecules or atoms or ions or electrons or something, not nothing.
The talker has found a hearer but not a listener; and though he may talk his very best for his own sake, you will find that his mental movements are erratic: they have no fixed centre and no definite object. His talk is like the water of a canal whose banks have given way, which rolls aimlessly hither and thither, without fulfilling any useful function, though it is the same water which was so helpful and serviceable, when it was confined within clearly marked limits by the restraining force of its earthy boundaries.
The foolish are like ripples on water, For whatsoever they do is quickly effaced; But the righteous are like carvings upon stone, For their smallest act is durable.
The seed of mystery lies in muddy water. How can I perceive this mystery? Water becomes clear through stillness. How can I become still? By flowing with the stream.
Of the good in you I can speak, but not of the evil. For what is evil but good tortured by its own hunger and thirst? Verily when good is hungry it seeks food even in dark caves, and when it thirsts it drinks even of dead waters.
If a writer of prose knows enough about what he is writing about he may omit things that he knows and the reader, if the writer is writing truly enough, will have a feeling of those things as strongly as though the writer had stated them. The dignity of movement of an iceberg is due to only one-eighth of it being above water. A writer who omits things because he does not know them only makes hollow places in his writing.