Finally, since the dramatic action was confined to a single day (however elastic) at the culmination of the story, it was rarely possible for the dramatis personae to experience any particular change or development of character during the course of the play. This fixity of type was not only a natural result of theatrical conditions in ancient times and of the use of masks but was also in thorough accord with Homeric conventions (see pp. 254 f., above). Moreover, it harmonized completely with the Greek fondness for schematization. Horace’s words in his _Ars Poetica_ are entirely Hellenic in spirit: “Either follow tradition, or invent that which shall be self-consistent. In the former case, let Achilles be impatient, irascible, ruthless, keen...; let Medea be untamed and unconquerable, Ino tearful, Ixion treacherous, Io ever roving, and Orestes in sorry plight. In the latter case, keep the character to the end of the play as it was at the beginning and let it be consistent” (vss. 119 ff.). All this implies more than we would think desirable today. Not only was a positive development into a character seemingly inharmonious with that seen at first rarely possible, but the singleness of purpose in ancient plays, which has been called the unity of mood (see p. 201, above), crowded out incidents which might have revealed other phases, no matter how consistent, of a dramatic personage’s character. The taste of some critics objected to even the slight modifications in rôle which ancient conditions did permit. For example, to modern readers the manner in which Medea, in Euripides’ tragedy of that name, wavers between love for her children and the desire to punish her recreant husband by murdering them is esteemed one of the finest touches in ancient drama. But the Greek argument which is prefixed to this play reports that “they blame Euripides because he did not maintain Medea’s rôle but allowed her to burst into tears as she plotted against Jason and his second wife.” Again, so excellent a critic as Aristotle cites the title rôle in Euripides’ _Iphigenia at Aulis_ as an example of inconsistency,[341] inasmuch as the Iphigenia who pleads for her life at vss. 1211 ff. in no wise resembles her later self, who willingly approaches the altar. To modern feeling, since the change is psychologically possible and is plausibly motived by the sudden realization that her death can serve her country, it seems entirely unobjectionable. But these two passages and the usual practice of the Greek stage reveal a discrepancy between the ancient and the modern points of view. The simplicity of character-drawing which resulted from Greek methods is strikingly described, in a different connection, by Mr. Cornford: