We see psychology basically as the study of trouble -- an attempt to discover reasons for unhappiness or destructive behavior, and the like. But a new, or rather revived, movement is more concerned with the other side, and proposes clinical examination of those who are happy and move easily in the world. PNS associate editor Walter Truett Anderson is the author of "The Future of the Self" (Tarcher Putnam, 1997).

Ask the average person what psychology is about and he or she is likely to answer that it's about mental illness -- anxiety, depression, obsession, compulsion, and so on down the long, bleak laundry list of human discontents. Unfortunately, the average person is likely to be dead-on right.

From Sigmund Freud to B. F. Skinner to the authors of today's Diagnostic and Statistical Manuals of Mental Disorders, mainstream psychology is mainly a matter of accentuating the negative. Sure, there have always been dissenting voices -- such as the late Abraham Maslow, who throughout the 1960s tried to get his colleagues to pay attention to peak experiences and self-actualizing people (that is, people who are healthy and fully functioning) -- but they have always been in the minority.

Establishment psychologists, on the whole, tend to get nervous when people start talking about such matters as love, optimism, joy, courage and kindness. All those subjects are dismissed as "pop psychology," more suitable for gushy self-help books than for serious scientific study.

But over the past couple of years, another group of dissidents has hoisted the flag under the name "positive psychology."

The leading spokesman and tactician of the new counter-movement is Dr. Martin Seligman of the University of Pennsylvania. Two years ago, during a term as president of the American Psychological Association, he accused his colleagues of having allowed their profession to turn into a "victimology." Most psychological research, he claimed, tends to regard human beings as little more than passive objects buffeted about by events, and most psychotherapies tend to treat mental illness "within a theoretical framework of repairing damaged habits, damaged drives, damaged childhoods and damaged brains."

"Psychology," he insisted, "is not just the study of weakness and damage, it is also the study of strength and virtue. Treatment is not just fixing what is broken, it is nurturing what is best within ourselves."

Different people who rally to the positive psychology cause have different ideas about what real mental health is and how it can best be cultivated. However, what basically unites them is the conviction that normal human beings possess a great deal more strength and resilience than they are usually given credit for, and that -- however much we may be affected by events beyond our control or by elements of our genetic heritage -- we are capable of making meaningful choices about what we do and how we feel.

Seligman's own favorite theme is optimism. He claims there is a significant body of evidence that optimistic people are happier and more productive than pessimists. Furthermore, he believes that optimism can be learned and taught. He has written books on this subject -- with titles such as "Learned Optimism" and "The Optimistic Child" -- and has even developed a curriculum for teaching practical optimism in the schools.

Another leader in the positive psychology movement is the Hungarian-born Mihalyi Csikszentmihalyi of the University of Chicago, whose thinking focuses on certain kinds of optimum experience he calls "flow." Flow is about the way people feel when they are doing something really well, or simply enjoying a pursuit so much that they lose themselves in it.

In Csikszentmihalyi's view, flow is as real a part of human life as, say, depression, and he believes that a better understanding of it -- grounded in hard research -- can change the way people do their work or, for that matter, their goofing off.

Research is an all-important part of the positive psychology movement, the means by which its leaders such as Seligman and Csikszentmihalyi -- and the many younger psychologists who are signing on to the cause -- hope to convert their colleagues. Research is also the means to distance themselves from the writers of spiritual chicken soup books, and find some practical ways to increase the human sum of joy, hope, strength and courage while we busy ourselves making so many kinds of progress in the world.