The “D” word—not Davos, but depression—ruled conversation at a dinner hosted by Corporate Knights and Innovest and headlined by George Soros, Joseph Stiglitz, and Lord Nicholas Stern. 

Much of the talk at Davos this week has been whether or not the world is hurtling toward a global depression. While there is great concern over when and how fully the economy will rebound, it’s also easy to get caught here in an echo chamber, creating an endless feedback loop that reinforces and magnifies conventional wisdom but ignores weak signals that may actually be better predictors of what’s to come.

The dinner featured a lively debate, joined also by Laura Tyson, a member of Obama’s transition team and former chair of Clinton’s Council of Economic Advisors, and Daniel Esty, a professor of environmental law and policy at Yale.

Much of the talk centered on whether the new U.S. administration could truly take the lead on climate in 2009 in light of the economic meltdown. Soros and Tyson held a fairly pessimistic view of what the U.S. political debate will allow. Soros thinks the window to put a price on carbon has closed based on plummeting energy prices. Tyson lavished praise on Obama’s energy and environment team, but worries that the premium on securing support for the U.S. stimulus package won’t enable a truly green package.

Lord Stern carried the banner for quick action leading up to the Copenhagen Conference in December. He believes that we will know what is possible in the next two to three months, which will determine the success of Copenhagen and, ultimately, whether the world turns toward cooperative action to combat climate change.

Esty landed somewhere in the middle. He is pessimistic that a global deal will be achieved this year but optimistic that the new U.S. administration will make a major commitment to leadership that will yield fruit in the next couple years.

On a more upbeat note: Al Gore was in fine form at a reception hosted by his investment firm, Generation Asset Management, and VC heavyweight Kleiner Perkins. After opening remarks that were in turn hilarious, spiritual, and politically hard-headed, the “Goracle” said that he hears from White House staff hourly.

His conclusion about the new president? “At climate change meetings, President Obama is the greenest, most dedicated person in the room.”