Poetry is not magic. In so far as poetry, or any other of the arts, can be said to have an ulterior purpose, it is, by telling the truth, to disenchant and disintoxicate.
Catharsis is properly effected, not by works of art, but by religious rites. It is also effected, usually improperly, by bull-fights, professional football matches, bad movies, military bands and monster rallies at which ten thousand girl guides form themselves into a model of the national flag.
The condition of mankind is, and has always been, so miserable and depraved that, if anyone were to say to the poet: “For God’s sake stop singing and do something useful like putting on the kettle or fetching bandages,” what just reason could he give for refusing? But nobody says this. The self-appointed unqualified nurse says: “You are to sing the patient a song which will make him believe that I, and I alone, can cure him. If you can’t or won’t, I shall confiscate your passport and send you to the mines.” And the poor patient in his delirium cries: “Please sing me a song which will give me sweet dreams instead of nightmares. If you succeed, I will give you a penthouse in New York or a ranch in Arizona.”