Do you see the glass as half-ful rather than half-empty? Do you keep your eyes upon the doughnut , not upon the hole .Suddenly these cliches are scientific questions , as resesrchers scrutinize the power of positive thinking .

A fast-growing boby of research----104 studies so far , involving some 15000 people----is proving that optimism can help you to be happier ,healthier and more successful . Pessimism leads , by contrast , to hopelessness , sickness and failure , and is linked to depression , loneliness and painful shyness . “If we could teach people to think more positvely” says paychologist Craig A .Anderson of Rice Uniersity in Houston , “it would be like inoculating them against these mental ills .

“Your abilities count ,” explains psychologist Michael F . Scheier of Carnegie-Mellon University in Pittsburgh , “ but the belief that you can succeed affects whether or not you will” . In part , that's because opti mists and pessimists deal with the same challenges and disappointments in very different ways .

Take , for example ,your jib . In a major study , psychologist Marin E . P . Seligman of the Unversity of Pennsylvania and colleague Peter Schulman surveyed sales representatives at the Metropoliatn Life Insurance Co . They found that the positive-thinkers among representatives sold 37 percent more insurance than did the negative thinkers . Of newly hired representatives , optimists sold 20 percent more .

How did they do it ? The secret to an optimist's success , according to Seligman , is in his “explanatory style” . When things go wrong the pessimist tends to blame hinself . “I'm no good at this ,” he says . “ I always fail .” The optimist looks for loopholes . He blames the weather , the phone connection , even the other person .