THE diction of the huge company assembled in Robert Chapman's production of Ceasar and Cleopatra is the finest I have ever heard in the vault of the Loeb mainstage auditorium. Every word and phrase spoken is clear, and the balance of voices is carefully, even scrupulously, maintained. A technical point of this sort may seem a strange point of departure for more general praise of this staging of Shaw's ideological spectacular, particularly since such matters as diction are always more notable for their lack than their presence. But the virtue of this Caesar and Cleopatra lies in the words--the glorious, humble, funny words-- and in the good faith, taste, and intelligence in which those words are delivered to an audience. There are some nits abroad in the production, and it will be necessary to pick a few of them here. But no litany of unfortunate incidental, especially the brief one this staging provokes, can offset the qualities of honesty and judgment which mark both direction and performances, nor the pleasure which those qualities should be providing Cambridge audiences in the next two weeks.

The play is a curious animal: a comic rehearsal of serious ideas, tricked out like an operatic or cinematic spectacular. The intellectual substance (and thus, the dramatic substance, for after all, this is Shaw) of the play is contained in a series of richly humorous but intimate conversations, between two, three, or four major characters. These are scenes directed primarily at the ear, and it is in them that the production is at its best. Eddying about the pivotal encounters, however, is Shaw's depiction of the varied and colorful life of the Egyptian court and Roman camp. These physical details call for the best sort of visualization and stage realization, and I wonder how much they would contribute either to the dramatic argument or the comic effect of the play in even the best production. Significantly, and not too unhappily, it is in this area the production is weakest.

WHICH is not to say the production lacks a sense of designed visual coherence. Although the settings themselves (for which no program credit is provided) are neither beautiful, flexible, nor functional--consisting largely of sliding stair units and walls bearing faded and indifferently rendered Egyptian wall motifs--the use Chapman makes of them is bold and consistent. Given an almost unnaturally broad and shallow stage, he has chosen to arrange almost every scene as a balanced static composition, varied only at moments of true dramatic necessity. The effect seems to me to be entirely intentional, and it works splendidly in the frequent crowd scenes, when the groupings suggest at once the linear composition of classical art, and the luxury of a Cinemascope biblical epic. This is due in good part to Olga Liepmann's costumes, which make up in variety and color whatever they may lack in real period style. But in the intimate scenes, the static principle is a good deal less successful. The compositions satisfy when first revealed, but one soon begins to long for motion and depth, for a visual variety to match the energy of Shaw's verbal and intellectual movement. It may be that the actors are asked to rely on the text for more than even such an elegant text can provide.

On the whole, though, the company has been directed to play that text for all it is worth, and most of the principals are equal to the task. As an ensemble, they share only one common fault, perhaps an inevitable consequence of the production's drive for lucidity: at one time or another, most of the actors show a tendency to declaim rather than converse. As a result, the overall pacing of dialogue is sometimes slowed, and an occasional moment of insight or laughter is dimmed by pretentious delivery. Far more often, however, the line readings succeed in translating Shaw's stylized dialogue exchanges into natural and convincing scenes.

MOST gifted in this alchemical effort are Daniel Seltzer as Caesar, and Susan Yakutis as Cleopatra. Seltzer's performance is especially impressive: not only are his readings rapid and controlled, but he succeeds in underplaying effectively a role which would tempt any actor to bravado. As the ultimate embodiment of the Shavian pragmatic, democratic, sympathetic Superman, he also manages to convey a vision of humility in majesty. Further, his discipline deserves to underline the character's moments of wit and emotion, and to set the lonely Caesar apart from the more broadly drawn figures who surround him. The greatest virtues of the performance are, however, confined largely to scenes of dialogue. In Caesar's relatively few longer set speeches, Seltzer tends to lapse into a rhetorical and inflectionally rigid style of speech which contributes little to his readings.

Where Caesar is magnificently consistent, Cleopatra is a little anthology of feminine character. In the course of the play she not only matures from kitten to queen, but exercises her option for whimsical action to the fullest. Miss Yakutis handles the various phases, moods, and transitions with considerable skill, and like Seltzer she shines in the scenes of intimate conversation. My only objection to her portrayal is that it leans something too heavily on the prop of youth. Even at her first meeting with Caesar, Cleopatra must be something more than girlish--she must demonstrate a potential for rule. In her final scenes, she must possess at times a terrifying and self-possessed maturity. These qualities are all present in Miss Yakutis's performance, but do not always receive proper emphasis.

The cast is simply too large to do its members individual justice. But special mention must be made of Sheila Hart and Arthur Friedman (Ftatateeta and Pothinus). Their overbearing presences manage to evoke most of the corruption and tension in the atmosphere of the Egyptian court. Ed Etsten (Rufio) is physically and vocally perfect as Caesar's comrade-in-arms, though his performance lacks a good deal for variety. And when Leland Moss (Brittanus) drops the strange, epicene mannerisms which he has imposed on the character of the super-sophisticated reform barbarian, he has several moments of rare and special dignity.

Honesty and intelligence may seem to be terms of praise more suited to serious drama than comedy. But these are precisely the qualities lacking from too much stage comedy, and especially from comedy of ideas. An audience must be able to laugh, but it must also be able to respect itself and the object of its amusement afterwards. Among the many, many moments of laughter in this Caesar and Cleopatra, none is cheapened or distorted. And that is an accomplishment in itself.