(FORTUNE Magazine) – Is the world getting better or worse?

That was the first of a few big questions we asked 225 businesspeople, scientists, government officials, do-gooders, and other interesting folks from around the world before they arrived in Aspen for the Brainstorm conference hosted by FORTUNE and the Aspen Institute at the end of July. Their written responses told a lot about how the conference would unfold as well as the unsettled--and unsettling--state of the world.

U.S. business types were just about the only ones to out themselves as full-fledged optimists. "The world's getting better," wrote aggressively upbeat, aggressively bald marketing guru Seth Godin. "What's getting worse is our pessimism, our addiction to bad-news media, and our nerves." Go, Seth! A more typical response was that of opinion diva Arianna Huffington: "The world is both getting better and getting worse." There was outright gloom too: "The economy worldwide is not growing," wrote one of the Arab world's most prominent businesswomen, Lubna al Qasimi, of Dubai. "Poverty is on the increase. Illiteracy is on the rise."

All that may be testimony to the congenital and so often triumphant optimism of the American entrepreneur in a world lousy with pessimists. Then again, it may be that Americans are totally out of touch.

This was the third Aspen conference hosted by FORTUNE (but our first with the Aspen Institute; for more on the conference, including webcasts, see fortune.com). And while anxiously pondering the fate of the earth is always on the agenda at such gatherings, pessimism was especially thick this year. So was exasperation with the U.S. "Yes, of course, you are the strongest kid on the block--you have always been," chided Stefan Aust, editor-in-chief of the German newsweekly Der Spiegel, in a brief talk to the group. "But please refrain from acting like a class bully every single day."

There was a way to escape from the gloom and sourness, though. Most of Brainstorm's big events took place in a tent on the bucolic grounds of the Aspen Meadows conference center. Walk outside and you could soak in not only mountain splendor and really thin air, but also the sight of inventor Dean Kamen showing off a device he's developed that--if only he can get the price down--could provide electricity and clean water to the world's poor. Kamen, who was also offering rides on his Segway scooters, of course, was on the left as you left the tent. To the right was irrepressible Idealab chief Bill Gross, this time peddling not money-burning dot-coms but a cheap little solar-powered generator that he hopes will become a Third World staple. In other words, those incorrigibly optimistic American entrepreneurs--with their abiding faith that technology can solve the world's ills--haven't disappeared from the scene just yet.

The pages that follow offer a sampling of Brainstorm's people and themes. We recount the profoundly gloomy views of Australian arms-control guru Richard Butler on the unraveling of nuclear nonproliferation agreements and take a look at the ramifications of growing anti-Americanism for U.S. multinationals. We also describe Kamen's power and water dream (or pipe dream, perhaps), as well as an already successful, and profitable, effort to provide innovative, ultra-low-cost medical devices in countries where only the rich can afford conventional models.

Shorthand descriptions don't really do justice to all that went on at Brainstorm. It was a conference where you could see and hear tech entrepreneur and big-time George Bush backer Gregory Slayton engage former President Bill Clinton in what turned into a not entirely civil discussion of political civility. Where Rwandan President Paul Kagame was able to campaign for reelection 9,000 miles from home by getting state-owned TV to report on his every Aspen move. (He won, three weeks later, with 95% of the vote.) Where, when participants introduced themselves and told what they did for a living on the first morning of the conference, a youngish-looking woman in blue jeans got the biggest laugh by saying, "Noor al Hussein. Queen." And where the Reverend Peter Gomes of Harvard's Memorial Church enraptured his fellow Brainstormers with a philippic against religious fundamentalism. "Which is more dangerous, a surplus of virtue or a surplus of vice?" he asked, paraphrasing an old saying. "A surplus of virtue, because conscience provides no check."

Charles Schwab CEO Dave Pottruck embodied as well as anyone the conference's mix of gloominess shot through with shafts of optimism. In a brief speech on Brainstorm's opening night he declared that he was "horrified" by the growing gap between "haves and have-nots" in the U.S. The next day, during a panel on CEO power, he complained that that executive compensation "has run completely amok." But he also cited the Internet, the mapping of the genome, and the fall of communism as evidence that life on earth is getting better.

In sum, you just can't get too down on the world at an event where former Texas governor Ann Richards and the then-not-yet-declared presidential candidate Wesley Clark ride around on the then-not-yet-recalled Segways. So we'll leave with two optimistic (sort of) notes from conference participants. "I believe that for the first time we can begin to map a future which is free of disease and ultimately free of death," William Haseltine, CEO of Human Genome Sciences, told a startled crowd. And in his written answer to one of those big questions we posed before the conference, Ilan Chet, president of Israel's Weizmann Institute of Science, said, "The world has nothing to fear--it has existed long before us and will continue to exist no matter what humankind might do. The world may find further assurance in a study made by a Weizmann Institute scientist describing a microbe that can withstand up to 3,000 times more radiation than can be withstood by humans." Consider yourself, and your microbe friends, reassured.

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