Though it sometimes seems shut up in schoolboy definitions and is a little roopy in its overall drive, Cyrus Hoy's first critical effort- an ""investigation into the nature of comedy, tragedy and tragicomedy""- comes off, at its best, with flying colors. Imposing in intent, rich in though as well as research, it is- even during a year which has seen two landmarks in dramatic criticism (those from Lionel Abel and Maurice Valency)- a work of considerable rewards. It jolts the reader out of his cubbyholed convictions and often sends him back to the plays themselves. Its Kierkegaardian dictum (contradiction inherent in the human condition is the common denominator of tears and laughter, and the reaction to the ideal and the real is the difference between)- is illuminated through the works of Euripides and Shakespeare, Jonson and Moliere, Ibsen and Pirandello, Ionesco and Beckett. Hoy's untiring understanding of the Elizabethan and Jacobean temperament is everywhere evident; and with The Wild Duck and The Tempest he is especially discerning and full of little discoveries. His discussion of today's anti-theatre suffers from limitations: surely he should have considered Brecht and Genet. The title is from Strindberg's Ghost Sonata: the Student in the Hyacinth Room envisioning the reconciliation of earth and heaven, Hoy's beyond-tragedy conclusion.