Not only does he sing about honesty, empathy, respect and optimism, he lives his life that way.

Based on the participants' answers about optimism, researchers divided them into four groups according to their level of optimism.

Commodity stocks were also hit as doubts grew about recent optimism that the global recession may have turned the corner.

A look at the background, however, raises questions about such optimism.

He wouldn't be specific about optimism or pessimism at the table.

"We take what the original architects were trying to say about optimism and give it a push."

But there was one encouraging sign in the flood of blather about optimism.

"This suggests that there's something we didn't measure about optimism that explains the immune system effects," she said.

"I think you're right about optimism getting the better of reason, Tom," Giscard replied.

"It is an end-of-the-century comedy about faith and optimism," he said.