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.
There is no room for the impurities of literature in an essay.... the essay must be pure--pure like water or pure like wine, but pure from dullness, deadness, and deposits of extraneous matter.
What is significant in one's own existence one is hardly aware, and it certainly should not bother the other fellow. What does a fish know about the water in which he swims all his life?