It was the purpose of this study (1) to discover the similarities and dissimilarities in three ancient Greek plays that used the legend of the house of Atreus as the basis for their plots; (2) to discover how these similarities and dissimilarities illustrate separate points of view concerning man, the universe and man’s place in that universe; and (3) to discover what relationship if any exists between the points of view expressed and the particular moment in history at which each playwright wrote. The plays considered were the Oresteia, a trilogy by Aeschylus first presented about 458 B.C.; Electra by Sophocles; probably presented first sometime before 413 B.C.; and Electra by Euripides, first presented in 413 B.C. SInce the purpose of the study was to compare ideas and points of view expressed by the three great tragic dramatists of Greece, no attempt was made to justify the plays selected as works of art nor their authors as master craftsmen. However, in cases where translators disagree or left out portions of the manuscript which seemed to be mistakes in copying or lapses in artistry on the part of the playwright, the investigator adopted the attitude expressed by H.D.F. Kitto. All the plays were read in translation, but where more than one translation was available at least two translations were read, one literal and one poetic; in some cases as many as three were read in an effort to insure accuracy.