The worst of these is to intend the action with full knowledge and not to perform it. That outrages the feelings and is not tragic, for there is no calamity. So nobody does that, except occasionally, as, for instance, Haemon and Creon Haemon, discovered by his father Creon embracing the dead body of Antigone, drew his sword on him but missed his aim and Creon fled. in the Antigone . Next comes the doing of the deed. It is better to act in ignorance and discover afterwards. Our feelings are not outraged and the discovery is startling. Best of all is the last; in the Cresphontes , By Euripides. Polyphontes killed Cresphontes, king of Messenia , and gained possession of his kingdom and his wife, Merope. She had concealed her son, Aepytus, in Arcadia , and when he returned, seeking vengeance, she nearly killed him in ignorance but discovered who he was. He then killed Polyphontes and reigned in his stead. for instance, Merope intends to kill her son and does not kill him but discovers; and in the Iphigeneia In Tauris . See Aristot. Poet. 11.8 , note. the case of the sister and brother; and in the Helle Author and play unknown. the son discovers just as he is on the point of giving up his mother. So this is the reason, as was said above, See Aristot. Poet. 13.7 . why tragedies are about a few families. For in their experiments it was from no technical knowledge but purely by chance that they found out how to produce such an effect in their stories. So they are obliged to have recourse to those families in which such calamities befell. See Aristot. Poet. 9.8 , note.