The role of the paralyzed sculptor who argues his right to choose suicide in "Whose Life Is It Anyway?" already has won Tony awards for two performers -- Tom Conti and Mary Tyler Moore.

Now, in a production that opened at the Kennedy Center on Saturday evening, Michael Moriarty comes to the lead role, one that depends so much on the interpretation of the actor and director.

His Ken Harrision is a man who chooses to go coolly, if not necessarily gently, into the night. He is a witty, intelligent man who makes a rationale, reasonable decision. "I'd rather not go on living like this with so much effort for so little result," he says with unemotional matter-of-factness.

The play opens with Moriarty on his hospital bed, waiting to be turned, rubbed, washed, shaved, fed, and jollied by the briskly cheerful hospital staff. Harrision, the sculptor, has been paralyzed from the neck down from injuries suffered in an automobile accident six months earlier. As he argues while refusing to take tranquilizers, the only thing left to him is his consciousness and he doesn't want to lose the ability to exercise that right.

His physician, Dr. Emerson, a man who is authoritarian in exercising his responsibility to save lives, feels that he can make the paralzed sculptor "accept" his condition of life if his patient can get through the initial bout of depression. Harrision, lying helpless in bed, unable even to argue against an injection of tranquilizer, decides to press a legal suit to have himself discharged from the hospital and detached from the catheter that keeps him alive. But first he must prove that he is sane and that it is a rational decision.

The tension and suspense in Brian Clark's play comes from the uncertainty of our own emotions -- how we feel about a human being's decision not to go on living anymore.

Moriarty's paralyzed sculptor is a lively, intelligent man with a mischievous wit. Underneath his banter with the hospital staff lies a bitter mockery. "How marvelous!" he gushes, ironically echoing the forced cheerfulness of a nurse. The juices still flow in Moriarty's paralyzed body. He glances longingly at a woman's breast underneath her white doctor's coat.

Moriarty gives us a man who makes a cerebral decision. One has to respect his intelligence and courage. But -- and I think this is a fault of interpretation -- we do not feel searing anguish that this man has made the decision that he doesn't want to live.

With Moriarty's paralyzed sculptor, we feel that he has made the right decision. Never are our feelings engaged enough for us to ask whether it might be the wrong decision, whether this is a person who should go on living.

There is one outburst of rage in an interview with a psychiatrist. It is only in the last few moments of the play that Moriarty's character drops his cool to reach out to our emotions. This comes when Dr. Emerson, who has been ordered by a judge to discharge his patient, tells Harrision that he may stay at the hospital and the life-supporting catheter will be removed to bring death in three to six days. Emerson explains that he will do this in the hospital because he still hopes Harrision may change his mind and decide to live.

"I won't. I won't," the paralyzed man replies. Moriarty voice wavers and breaks for the shattering moment at the end.

Since I have not seen the other performances in "Whose Life Is It Anyway?" I can only judge the production now on the stage at the Kennedy Center Eisenhower Theater. It is engrossing theater. But it is not the emotion-draining experience that others have talked about in seeing previous productions.

Brian Clark's play was first staged here in 1978 at the Folger Theater with John Neville-Andrews in the role. It then went on to Broadway with Conti in the lead role in the spring of 1979. It was refashioned for a woman to play the paralyzed sculptor when Mary Tyler Moore appeared in a second production earlier this year.

It is a demanding role for an actor or actress. Lying in a hospital bed, motionless from the neck down, the performer must become an acting head. He must have a lively, expressive countenance to mirror emotions. Moriarty, who has given powerful performances with studied understatements, seems to feel contained in an acting situation that limits his expression to his round, slightly-cherubic face.

There are strong performances from the supporting cast. Jack Gwillim's doctor is a man stubbornly holding to a code that has taught him to save lives. The light touch of arrogance in the early part of the play is softened at the end when he offers to permit his paralyzed patient to stay at the hospital to die.

Others that contribute to the production are Ellen Tobie as the young doctor who tries to understand Harrison's feelings; May Jay as the brisk, starched head nurse who does what she can; Stephen Temperley as the young solicitor who argues Harrision's case; Gordon Chater as the judge who must decide if Harrison is sane; Hamilton Martin as the social worker given the task of "cheering up" the patient; Kathly Helmer and Basil A. Wallace, as young hospital workers, and David Tabor, Cyril Mallett, Michael Kolba, and Robert Rigamonti as assorted psychiatrists and lawyers.

"Whose Life Is It Anyway?" is at the Kennedy Center for a five-week engagement until July 27.