The 29th annual TED Conference in Long Beach, California, started as I remember several previous TEDs began: with two men with newly published books to sell proposing a future that was going to be either terrible or terrific. (The Economist ran this debate with the same protagonists on 12 January.) Since this was futurology, based on selective quotation of currently available data, there was no knockdown winner.

Still, later in the meeting, some pessimistic notes were struck that made you sit up and listen. Danny Hillis, computer guru, wondered whether too little attention had been paid to defending the internet itself. It’s vulnerable to mistakes and deliberate attacks; there are “a lot of bad guys out there.” We need a Plan B if and when it gets taken down, argued Hillis. Vint Cerf, “father of the internet,” thought that the internet would probably pull through. He’s proposed “clean sheet”—rethinking the internet as if it had never been built, and seeing whether any new ideas could be retrofitted into the existing architecture.

James Lyne, cyber security specialist, scared everyone with his account of the vulnerability of the electronic devices we so blithely use. Never again will I allege that media stories of security breaches have been planted by computer security companies trying to drum up business. (If Lyne hadn’t convinced me, a conversation with a fellow attendee who worked for a large bank would have—all large banks are now subject to relentless cyber attack.)

For me the highlight of day one was Bono—lead singer of U2, but at TED for his activism. The previous TED prizewinner talked about the successes of ONE (one.org), which pressures politicians to improve policies for the poorest. It was a wonderful antidote to the prevailing pessimism and the defeatism that blocks progress in the here and now.

Anxiety about education stalks TED and its attendees: two years ago I heard Bill Gates bewailing the state of education in California. Nobody thinks we’ve got education “right” anywhere for the present, let alone the near future. Education “heroes” pop up on most TED agendas—so much so that you wonder whether the “E” in TED stands for Education rather than Entertainment. This year’s agenda was no exception. Freeman Hrabowski, president of the University of Maryland, Baltimore, discussed how his university’s programme for high-achieving ethnic minority students in science and engineering has become a national model.

But the big news was the winner of the first million dollar TED prize: Sugata Mitra, who will be using the money to promote self organised learning environments. He was set on this path by watching what happened when computers were made available to Indian children who would never own a computer, didn’t speak any English, and didn’t know what the internet was. “It’s not about making learning happen; it’s about letting it happen,” he said. It didn’t seem a million miles from problem oriented learning, which has been a feature of medical school curricula for decades. Mitra was introduced by Sir Kenneth Robinson, whose own TED talk on education has been seen by a staggering 15 million people.

Elon Musk made a riveting interviewee in a session with TED curator, Chris Anderson. The shy serial entrepreneur co-founded PayPal, has overseen product development of the all-electric Tesla cars, and is the chief designer for Space-X, which develops spacecraft and reusable rockets. When asked how he managed all this he replied: “I work a lot.” That, and boiling things down to their fundamental truths.

This year’s theme was “The Young. The Wise. The Undiscovered.” and there was a group of youngsters whose TED talks triggered a host of questions about education. First off was 13 year old Masai, Richard Turere, who dismantled his mother’s household appliances to make a “lion light” to scare lions away from  the cattle he was meant to be minding. Next came Taylor Wilson, who at 14 became the youngest person to achieve nuclear fusion, a project that began in his garage. Working in Johns Hopkins laboratories, 15 year old Jack Andraka developed a test for the presence of mesothelin, a protein found in raised concentrations in pancreatic cancer. It involved the interaction of carbon nanotubules and antibodies to mesothelin.

It wasn’t only teenagers wowing the crowd. Stewart Brand, well known to the audience as the force behind such initiatives as the Whole Earth Catalog and the Long Now Foundation, spoke of his desire to “de-extinct” some of the animals that have disappeared from the planet. His project is called Revive and Restore, and there’s a TEDx event devoted to it on 15 March, which will be streamed. Everyone had the decency not to mention Jurassic Park.

There is no such thing as a typical TED talk, but this came close to it: wacky, deeply informed, and ultimately motivated by concern for the planet. Another was the talk by Ron Finley, guerilla vegetable gardener of South Central Los Angeles. He and his neighbours live in a food desert, with obesity rates five times those of Beverly Hills, some eight miles away. So Finley, and anyone he can interest, have taken to planting the vacant lots and roadsides of his neighbourhood with vegetables. His final challenge to the meeting was: “Don’t call me if you want to sit around in cushy chairs and have meetings where you talk about doing some shit…If you want to meet with me, come to the garden with your shovel so we can plant some shit.”

Its message wasn’t far from that of Bono’s talk the day before. Talking is fine—and there’s an awful lot of talking over the four days of a TED conference. But to change the world you’ve got to act.

The third day included three talks with a distinctly medical feel:

Daniel Reisel, a doctor and neuroendocrine researcher at University College London, has been working with psychopathic prisoners at Wormwood Scrubs, London. Are prisons, which haven’t changed for 100 years, the very worst places to attempt to rehabilitate this group, he wonders.

Rose George, a sanitation expert, has a message that is well known to BMJ readers—diarrhoeal diseases claim millions of lives and the answer is proper sanitation.

And Eleanor Longden, now a research psychologist, had a message that seemed highly threatening to orthodox psychiatry: She had climbed out of the depths of a psychotic illness and reached some sort of accommodation with the voices that had plagued her. Regarding them as “a sane reaction to insane circumstances” she has apparently adopted a similar explanatory framework as psychiatrist RD Laing.

The last day of the conference had one of my highlights—by social entrepreneur, Dan Pallotta. It’s hard to better what he said when discussing his latest book: “The nonprofit sector is critical to our dream of changing the world. Yet there is no greater injustice than the double standard that exists between the for-profit and nonprofit sectors. One gets to feasting on marketing, risk-taking, capital and financial incentive, the other is sentenced to begging.” Pallotta has earned the right to argue for bringing for-profit discipline and practices to charities—he helped raise $582 m from long distance AIDS cycle rides and breast cancer three day events.

Tony Delamothe is deputy editor, BMJ.