When an angry child announces plans to seek revenge, "forgive and forget" is the bromide most often offered by a parent, teacher, or elder sibling. For many of us, it's probably the earliest life lesson we remember being taught.

Even upon first hearing, though, this emotional package deal sounds excessive in its demands. In one fell swoop, is a crime not only absolved, but also stricken from the record? "No!" whines the aggrieved child or, for that matter, the vengeful adult, "It's one or the other. I can't do both."

What exactly is forgiveness? And should it necessarily be linked to forgetting? Under the direction of Dr. Everett L. Worthington Jr., answers to these questions are being sought anew through rigorous scientific research. Worthington, who is also chairman of the department of psychology at Virginia Commonwealth University, serves as executive director of A Campaign for Forgiveness Research. The Campaign, founded in 1997 with a $4 million grant from the John Templeton Foundation, and an additional $1.5 million from the Fetzer Foundation, initially awarded 33 grants to neuroscientists, psychologists, and sociologists around the world to study the spiritual and physical benefits of forgiveness.

The shared intent of these projects is to find ways by which forgiveness can be monitored and measured scientifically. Now, as the funded scientists conclude their multi-year studies, they are poised to announce startling discoveries about how forgiveness operates within diverse types of relationships, including that between husband and wife, parent and child, and citizens of "deeply divided" nations.

Even before its public release, the research has attracted both attention and praise from President Jimmy Carter, Dr. Robert Coles of Harvard University, and Dr. Martin Marty at the University of Chicago. Nobel Laureate and retired Archbishop Desmond Tutu has hailed in particular a study of forgiveness in post-apartheid South Africa that was conducted by Audrey R. Chapman, director of the Science and Human Rights program of the American Association for the Advancement of Science in Washington DC.

Everett Worthington never imagined such a wide-ranging interest in forgiveness when he initially became involved with the subject in the mid-1980s. At the time, he had found that his "hope-focused" method of conflict resolution wasn't working well for one of the married couple he was counseling. "The next time they came in, we tried a reversal. Rather than dwelling on what hurtful thing the partner had done, I had them hold hands, look at each other, and ask forgiveness for something they'd done," Worthington recalled. "Examining themselves to see how they provoked the other really turned their marriage around."

Finding this episode significant enough to publish in the journal Psychotherapy, Worthington also decided the phenomenon of forgiveness needed further scientific study. Starting in 1997, he recruited 150 pairs of newlyweds who, over the course of 18 months, were videotaped five separate times in two-part sessions. First, they were asked to discuss a topic they agreed about, then a subject on which they disagreed. During these conversations, the couples were electronically monitored to detect muscle tensing and tested for the increased presence of cortisole, a substance the body produces naturally in situations of high stress.

"It turns out there is a psychobiology to forgiveness. Transgressions are stressful, you see, and when a trauma happens such as a betrayal, the brain secretes cortisole which burns a memory," Worthington explained. "The idea to forgive and forget is crazy! Your whole body is telling you to remember this trauma, so it won't happen again."

"People who don't forgive, though, have a build up of cortisole," he continued. "This puts the body under stress, and every time they think about the wrong done them, there's even more stress." The only way out of this trap, Worthington believes, is through the power of empathy. When you think yourself wronged, he recommends, try to imagine what your partner was feeling at the time of the alleged transgression.

"In this behavior — replacing negative with positive emotions — there's a strong dose-response curve," he concluded. "The more 'medicine of forgiveness' you take, the more empathic response you get. I always say, 'learn to forgive because it's good for your health.'"

Another grant recipient, Dr. Kathleen Lawler, who is a professor of psychology at the University of Tennessee in Knoxville, made a similar finding. "My hypothesis that unforgiveness was a form of stress is what started me down this road," she said.

In a study of 120 college students Lawler monitored cardiovascular response as the students described the times they'd felt hurt by a loved one. "When you ask someone to recall a time of betrayal, their heart races. This is normal," Lawler said. "But for those who haven't forgiven the one who betrayed them, this cardiovascular arousal remains at an elevated level for much, much longer. It is such a strong correlation, in fact, it suggests that there's a strong link between unforgiveness and the illnesses associated with high blood pressure."

Dr. Frank Fincham, a University at Buffalo distinguished professor of psychology, embarked on a study, in 2000, of the correlation between unforgiveness and psychological aggression — or, verbal and non-physical abuse. Fincham recruited 96 couples who had long-term marriages to fill out detailed questionnaires. "What we found was that forgiveness decreases acts of psychological aggression in marriage," Fincham said, a finding he sees as important for two reasons. "Physical violence is always preceded by verbal abuse. And, victims say that the suffering from psychological aggression is worse than bruises and broken bones."

The battle of the sexes is not wholly dissimilar from civil war, suggested Audrey R. Chapman. "Unlike interpersonal relationships, however, where conflicts are usually worked out privately," she said, "societies often organize human rights tribunals to determine what happened, who caused the conflict, and how it can be avoided in the future."

Chapman's grant enabled her to study the success of South Africa's post-apartheid Truth and Reconciliation Commission to see what qualities of the human spirit promote forgiveness even when faced with a legacy of social, political and economic injustice. Her research led to the recent publication of Religion and Reconciliation in South Africa: Voices of Religious Leaders (Templeton Foundation Press, 2003), a book she co-authored with Reverend Bernard Spong.

"I've been very concerned for a long time about what I label 'deeply divided societies,'" Chapman said. "Whole countries have gone through traumatic divisions, usually based on identity issues such as race or ethnicity."

While there have been truth finding missions before — notably in Haiti, Guatemala and Uganda, South Africa was the first to promote reconciliation as an independent goal. Another signal difference was that South Africa's Truth and Reconciliation Commission was shaped by and imbued with religious content, and led by clerics such as Archbishop Desmond Tutu rather than lawyers and judges. Finally, South Africa took the unusual step of holding public hearings, so Chapman was able to obtain and scientifically analyze the stories from thousands of apartheid victims.

"How societies heal is far more complicated than what happens between individuals," she said. "It's not just victim and perpetrator, there are institutional levels, and repressive governments trying to maintain power. The option of forgiving and forgetting is not there, either. You can't go on to reconciliation without finding the truth of what happened in the past."

It is one of mankind's most healing balms. Yet, as these groundbreaking studies won't allow us to forget, the process by which forgiveness occurs is not a simple matter of saying "I'm sorry."

A Campaign for Forgiveness Research supports scientific inquiry and disseminates findings. Concurrent conferences, Scientific Findings about Forgiveness and Helping People Forgive are scheduled for October 24-25, 2003 in Atlanta, Georgia. More information is available on the web site: www.forgiving.org

Stephen Henderson, a writer based in New York City, contributes frequently to the New York Times, The Baltimore Sun, Town & Country, and Religion News Service, as well as other publications.