It's not cool to be pessimistic.
This is my conclusion after interviewing scores of thoughtful people who've wrapped their minds around the most vexing challenges facing humanity.
Economist Robert Reich, who focuses on growing inequality, says he remains optimistic even though the top one percent of income earners are enjoying 95 percent of the gains in the U.S since the last recession.
Scientist Tim Flannery, who has written extensively on climate change, has an optimistic view of how things might turn out for the world. This depends on Gaia protecting herself from the havoc being wreaked by her most intelligent species.
Similarly, environmentalist David Suzuki speaks bravely of humanity's chance of survival in the face of rising greenhouse gas emissions. What's required is more sensible decisions about the use of fossil fuels. He's also optimistic that the Fukushima nuclear disaster won't cause serious health problems for people who eat fish from the Pacific Ocean.
Gwynne Dyer has written hopefully about geo-engineering rolling back the climate crisis. All it will require is seeding the skies in certain ways to reflect some of the sunlight back into outer space.
Conservationist Tzeporah Berman seems to think if we work with well-intentioned corporate executives and elect climate-friendly governments, there's a chance of turning things around before some sort of environmental Armageddon.
Then there's economist Jeff Rubin, who has chronicled the depletion of conventional oil supplies. He often expresses optimism about how people will make do in a world with slow-to-no economic growth for the foreseeable future. He also believes international trade will plummet as energy costs increase, but hey, we'll adapt.
Meanwhile, media and entertainment executives maintain a cheery disposition even as they acknowledge how the Internet is eviscerating their businesses.
I spent a fair amount of my Saturday at a workshop with some brilliant young people seeking to enter the media. I'm guessing that they have taken on substantial debts to become educated in ways that I can only envy. Some spoke several foreign languages.
I'm not optimistic about all of them ending up in their chosen field.
Later that day, I attended the Amnesty International Film Festival, which featured a movie about brave Mexican journalists killed covering the war on drugs.
Mexico used to be such a peaceful country, but not any more.
It's hard to feel good about Mexico's future in the face of all of this violence.
I confess that I'm troubled by all the optimism I encounter from leading thinkers on inequality, climate change, overpopulation, and oil depletion.
Adding up all the variables, I've concluded that more global food shortages and increased famine are inevitable. Despite this, our premier plans to build a new bridge to Delta that will result in the loss of some of Canada's finest farmland.
Having a cheery disposition may make someone sound more pleasant in radio and television interviews.
It might even enhance a person's likelihood of obtaining book contracts, becoming a media or entertainment executive, or getting elected to high public office.
But it has a way of sugar-coating problems, diminishing the sense of urgency that we should all be feeling about these crises.