Is firewalking a case of mind over matter or a simple lesson in physics?
The 21 people treated for burns after walking over hot coals at a Tony Robbins motivational seminar last month may be rethinking the maxim that you really can do anything you put your mind to.
Firewalking has been around for thousands of years, but the University of London concluded in the 1930s that rather than being an exercise in mind over matter, success in this apparently mind-boggling feat lay in the low thermal conductivity of the burning wood and the short contact time between the hot coals and the person's feet.
The most obvious explanation is that those who were burned lingered a bit too long in one place while walking over the bed of hot coals...
So how did Robbins' seminar attendees get burnt?
Scientific American blogger Jennifer Ouellette says there must have been a problem with the way the exercise was conducted.
"The most obvious explanation is that those who were burned lingered a bit too long in one place while walking over the bed of hot coals... so maybe there was something not quite right with the set-up," she writes.
David Willey, a physics instructor at the University of Pittsburgh at Johnstown, is also a world record holder for the longest firewalk.
He writes: "What I believe happens when one walks on fire is that on each step the foot absorbs relatively little heat from the embers that are cooled, because they are poor conductors that do not have much internal energy to transmit as heat, and further that the layer of cooled charcoal between the foot and the rest of the hot embers insulates them from the coals.
"This is not to deny that one may feel empowered by having walked on fire, nor is it to dispute that it may improve self-confidence. I do however believe that firewalking is understandable in terms of basic physics and is not supernatural nor paranormal.”
They may not always protect us from fire, but can charismatic performers such as Robbins offer long-term improvement in people's lives?
Dr Sarah Edelman, a clinical psychologist and author of Change Your Thinking, has made it her business to find out.
She believes motivational talks can give participants a boost, but warns against expecting long-term results.
“The general view of psychology is that to actually get significant change in people's lives, you need ongoing reinforcement," she said. "For the majority of people who attend motivational programs it's like seeing a good movie or seeing something that makes you feel excited and interested but in the long term doesn't really impact on your life.”
The US motivational speaker Zig Ziglar acknowledges that external motivators are often short lived: “People often say that motivation doesn't last. Well, neither does bathing – that's why we recommend it daily.”
The fact is that motivational speakers such as Robbins still cater to a very real need, given most of us - even the most successful - periodically suffer from a lack of motivation.
And it's not only motivational speakers looking to cash in on our collective need to be inspired.
Using the Olympic Games as its muse, Qantas has been busy telling us that the reason it flies is for “all those who think anything is possible”. The Commonwealth Bank has joined the chorus, upgrading itself from mere bank to self-empowerment company with its "can" campaign, featuring Australian actress Toni Collette reading a poem.
With such wide-eyed optimism now being spruiked by blue-chip companies, the power of positive thought is obviously a message many of us are more than happy to accept at face value.
But considering seminar participants might be asked to part with large sums of money in the pursuit of their dreams, what sort of return on investment might they expect?
Robbins was certainly able to convince a group of people that the act of walking over hot coals is an exercise in restructuring one's mind and a meaningful metaphor for overcoming genuine adversity.
So what makes so many believe that such an activity is useful?
Edelman said it can be explained by the unquestioning group consensus that is often cultivated at these events. She believes this audience response is evident in Robbins' presentation 'Why we do what we do' - which is one of the most watched on the online talk platform TED.
"Robbins' presentation includes huge generalisations and clichés interspersed with self-evident truisms," she said.
"He skilfully engages the audience by asking 'motherhood' questions such as 'who else has been hurt in a relationship?' As he receives almost unanimous agreement to such questions he creates an atmosphere of group consensus where it feels like everyone in the room agrees with him. When individuals get caught up in the emotion generated by this style of presentation they respond emotionally and are less likely to engage critical thinking."
But is the quick and easy sense of optimism created by such presentations something that motivational speaking should apologise for?
Among all the cliches and tautology, it is hard to deny that the top tier of motivational speakers are able to make us reflect on the power of positivity and how to leverage it to improve our opportunities in life.
But while many motivational speakers can be quite motivating, Edelman said not everyone should expect the same results from attending these events.
“People who are already successful are successful because they are proactive and because they set goals for themselves. I think if you're someone who is open to new ideas and is constantly seeking and willing to take risks and set goals, you will probably be more likely to benefit from a motivational speaker.”
Just do a bit of research before you part with your money, she advises. Your feet may not get burnt but your wallet just might.