The sphere of this content,[46] although capable of great variety of detail, is not in its essential features very extensive. The principal source of opposition, which Sophocles in particular, in this respect following the lead of Æschylus, has accepted and worked out in the finest way, is that of the _body politic_, the opposition, that is, between ethical life in its social universality and the family as the natural ground of moral relations. These are the purest forces of tragic representation. It is, in short, the harmony of these spheres and the concordant action within the bounds of their realized content, which constitute the perfected reality of the moral life. In this respect I need only recall to recollection the "Seven before Thebes" of Æschylus and, as a yet stronger illustration, the "Antigone" of Sophocles. Antigone reverences the ties of blood-relationship, the gods of the nether world. Creon alone recognizes Zeus, the paramount Power of public life and the commonwealth. We come across a similar conflict in the "Iphigeneia in Aulis," as also in the "Agamemnon," the "Choephorae," and "Eumenides" of Æschylus, and in the "Electra" of Sophocles. Agamemnon, as king and leader of his army, sacrifices his daughter in the interest of the Greek folk and the Trojan expedition. He shatters thereby the bond of love as between himself and his daughter and wife, which Clytemnestra retains in the depths of a mother's heart, and in revenge prepares an ignominious death for her husband on his return. Orestes, their son, respects his mother, but is bound to represent the right of his father, the king, and strikes dead the mother who bore him. A content of this type retains its force through all times, and its presentation, despite all difference of nationality, vitally arrests our human and artistic sympathies.