It seems clear to me that Aristotle is thinking of the tragic pensiveness that comes over the spectator at a tragedy. But pensiveness is a kind of relief and resolution, in which pain and pleasure are peculiarly mixed. How can Aristotle call this condition a purification? What is the impure element in feeling, and how is it removed in the tragic emotion? It seems to me that the answer is as follows: being overcome by misery and horror involves a painful division. There is a disjunction from what is happening, a refusal to accept that rebels against the agonizing events. But the effect of the tragic catastrophe is precisely to dissolve the disjunction from what is. It effects the total liberation of the constrained heart. We are freed not only from the spell in which the misery and horror of the tragic fate had bound us, but at the same time we are free from everything that divides us from what is.
Should we not recoil in horror at the miserable fate of losing a sense of misery and horror? If someone fails to rebel against and refuse to accept the "agonizing events" of the 9/11 attacks, or the holocaust of unborn children in America and throughout the world, is this not something inhuman? Why then should we attend and foster the birth of such a terrible beauty as accomplishes this purgation of feeling?