Peter Brook directs Chekhov

``What is essential is to see that these plays are not about lethargic people,'' writes Peter Brook about Chekhov's characters. ``They are hypervital people in a lethargic world, forced to dramatize the minutest happening out of a passionate desire to live.'' True enough, and neatly put. Mr. Brook also quotes Chekhov's observation - which frequently applies to Chekhov's own work - that in the greatest writing, ``you feel life as it should be in addition to life as it is, and you are captivated by it.''

These admirable statements point up qualities that have made Chekhov's plays a living force in world theater for a century. ``I am a man of the '80s,'' says a character in ``The Cherry Orchard,'' and he gets a laugh partly because he seems as contemporary a personality in 1988 as he must have in Chekhov's own '80s. The story seems equally pungent today, with its rich interactions among men and women on a dignified but doomed estate, all of them in various stages of moral and emotional uncertainty.

The vitality of Chekhov's characters doesn't seem as full blown and persuasive as it might, however, in Brook's current production of ``The Cherry Orchard,'' an all-star affair (using Elisaveta Lavrova's fine English translation) that runs through April 10 at the Brooklyn Academy of Music's Majestic Theater.

For the most part, the shortcomings aren't directly the fault of the actors. They are a talented lot as well as a distinguished one. And they've clearly worked at merging their diverse approaches (and accents) into an integrated and reasonably seamless ensemble performance.

So why don't their efforts quite sustain the Chekhovian sense of mingled comedy and tragedy - of fervent intuitions, self-generated drama, simmering passion for life's possibilities - as consistently as one hopes they will? Responsibility must lie with director Brook, who apparently wants his audience to meditate on the play instead of getting caught up in the complex emotional charge that's embedded in it. The result is an absorbing but oddly dispassionate evening.

True to what has become his usual form, Brook has staged ``The Cherry Orchard'' as a minimalist magic-carpet ride: The floor is covered with his trademark Asian-style rugs, and otherwise there's little in the way of d'ecor or furnishing except what's essential to the action. This radical simplicity suits the profoundly human preoccupations of Chekhov's drama, which doesn't call for the visual punctuation (and ornamentation) that's a staple in most contemporary theater.

Such refinement makes for a productive approach to classic drama when the words and actions of the play are allowed to build an unflagging momentum. This is a challenge for the director and the performers. In this case, moreover, Brook has escalated the challenge in two ways: by using the broad, deliberately stark stage of the Majestic; and by presenting the play as a continuous, movielike story with no intermission.

Some of the cast members are fully capable of turning these circumstances to their own - and the audience's - advantage. Natasha Parry (as Lyubov) and Zeljko Ivanek (as Trofimov, the ``eternal student'') have mastered verbal and gestural nuances that are profoundly Chekhovian in mood and spirit. Brian Dennehy has many strong moments as the merchant Lopakhin, and it would be hard to overpraise the sad wit and witty sadness of Erland Josephson as Gaev. Special mention also goes to Roberts Blossom as the family retainer and to Linda Hunt, who makes the small role of Charlotta into a memorable experience.

Yet even these talented performers - and such colleagues as Kate Mailer, Mike Nussbaum, and Stephanie Roth - fail to generate the unstoppable dramatic energy that this ``The Cherry Orchard'' needs to propel it across the Majestic's wide-open spaces for 2 nonstop hours. There are also some surprisingly feeble ideas in the staging: People keep sinking to their knees and flopping on the floor, and many of the attempts at physical humor are pathetically clumsy.

Add these problems together, and one has an evening that can be deemed only partly successful. ``The Cherry Orchard'' remains a mighty play, and Peter Brook remains a director of uncommon intellectual rigor. But this production realizes only some of its own possibilities.