A poem, to my mind, creates visible or auditory forms for something that is invisible, which is the feeling, or the emotion, or the metaphysical content of a moment. Now it may also include action, but its attack is what I call the ‘vertical’ attack, and this may be a little bit clearer if you will contrast it to what I would call the ‘horizontal’ attack of a drama, which is concerned with the development from situation to situation, whereas a poem is concerned with the development, let’s say, within a very small situation from feeling to feeling.