Firewalk Mishap
According to reports, 21 people had to be treated for burns from walking over hot coals at a Tony Robbins inspirational event.
Robbins is a successful self-help guru with a schtick that depends upon the scientific illiteracy of his audience. After a session of telling people how to “unleash the power within” he demonstrates their new-found power by inviting them to walk barefoot over hot burning coals while thinking about cool moss. This is meant to demonstrate the power of mind over matter. This is, of course, nonsense.
The Hot Coal Deception
Many physicists have used the hot coal demonstration to teach a bit of elementary physics, as there is a very simple explanation for how people can walk over hot coals in their bare feet. I have, in fact, heard three (non-exclusive) explanations. The first, and the one that I think is probably the biggest factor, is that wood coals have a very low thermal capacity and conductivity. This means that they do not hold on to a lot of heat energy, and they conduct that energy very slowly. Therefore little heat is transferred to the soles of the feet – if you walk briskly across them and give little time for heat transfer.
Compare this to other substances with very different thermal properties. Aluminum is interesting because it has a very high thermal conductance (250 W/(m.oC)), but it has a very low thermal capacity. Iron has a thermal conductance of 80, but with a much higher capacity than aluminum. This is why aluminum cookware will cool down very quickly – even moments after you take it out of a hot oven it will be cool enough to touch. An iron pan, however, will take a long time to cool down once it has heated up.
Compare this to the thermal conductance of wood (specifically oak) – 0.07 W/(m.oC). This is tiny. So even though the coals are about 1,500 degrees F, not much of that heat gets transferred to the feet. You would not, of course, want to walk across a slab of iron heated to the same temperature, or even much less. I would rather walk across wood at 1,500 degrees than iron at 200 degrees.
That is enough to explain how a brisk walk across burning wood coals can be safe, but there are two other contributing factors. One is the ash that builds up on top of the burning coals. Ash is a good insulator, and a thin layer of it is enough to slow down heat transfer even further. This could explain why some people at the event were burned and others were not – how disturbed the layer of ash was before an individual walker went across.
A third factor that I’ve heard used to explain the phenomenon (I am not sure how much of a contribution this is) is perspiration on the bottom of the feet, which evaporates and causes a bit of an insulating barrier as well. This seems like the least consistent and important factor of the three.
None of this, of course, has anything to do with the power of the mind. You can think of hot burning lava while walking over the coals, rather than cool moss, and it won’t make a bit of difference. It is the laws of physics that protect your feet, not the ramblings of a self-help guru.
Ramblings of a self-help guru
Speaking of which, what is it, exactly, that Robbins is selling? I think Lisa Simpson summed it up best when she said of a similar character:
“This is madness. He’s just peddling a bunch of easy answers.”
Robbins promises:
Your success coaching plan is your “Pathway to Power.” It is not based on hope. It is not based on theory. It is modeled after those who have already achieved the real results you desire through life success coaching, at the highest and deepest levels.
Life coaching and self-help programs like this are generally not evidence-based in any meaningful way. They are usually just based upon a few simple ideas or catch phrases. They all have a common element, however – spending time thinking about your life, your goals, and how you deal with the people in your life. For anyone who is mostly coasting through life without much introspection, spending a weekend thinking about how to get motivated, achieve one’s goals, and make real changes is one’s life can be a profound experience. That’s the real hook. The details don’t matter.
Wrap that up with some common sense, that “motivational speaker” personality, and a good gimmick and you will probably do well as a self-styled life coach.
Richard Wiseman has done an excellent job of debunking the self-help industry in his book 59 seconds. Most of the advice and “easy answers” that are being peddled is not only improvised, it’s largely wrong. We have decades of psychological studies that actually provide evidence for which strategies are likely to be more successful, and often the real answers are counter-intuitive.
For example, you should not praise a child when they accomplish something. This sounds crazy at first – how can it be wrong to praise a child when they do something good? The problem is praising the result, rather than the effort. This can make children anxious, because they think they will only get praise and acceptance when they do well, something they cannot always control. What they can control is the amount of effort they put into something, so that is what you should praise (even if the result was less then stellar).
What is frustrating is that there is actually a great deal of published evidence that can inform the very questions raised by the self-help industry, but the big sellers in the self-help industry seem to be completely disconnected from that evidence. What they are selling are made-up easy answers, personality, and gimmicks.
It’s all the more annoying when the gimmick is based upon a misunderstanding of basic physics.
“What they can control is the amount of effort they put into something, so that is what you should praise (even if they result was less then stellar).”
Unfortunately, real life doesn’t give “an A for effort.”
How much evidence-based advice is based on contrived little lab experiments typically done on college students?
Max – that is a good point. It is very difficult to do well-designed psychological experiments like this – but not impossible. There is pretty robust research on this question. Here is a good summary with references: http://www.apa.org/education/k12/using-praise.aspx
The bottom line is that if your goal is to change behavior than you need to give specific praise for variables under an individual’s control.
I taught my kids that there are two kinds of fun: the easy and the hard. Easy has immediate payoffs – playing a game, watching a movie, etc. Hard fun is difficult, sometimes painful and frustrating, and the payoff only comes at the end, when you accomplish what you set out to do, or come close after your best efforts.
They must have been listening – they are both doing well in great universities.
Robbins Research International said in a written statement that 6000 attendees of the event walked across the coals Thursday. I’d be impressed if nobody got burned. What did they think when they saw people get burned, that the losers forgot to think about cool moss? Do firewalkers think they can touch a hot frying pan?
I don’t buy the foot sweat hypothesis. It shouldn’t evaporate, it should turn to steam and burn you. Ever put a wet pan on a hot stove? It doesn’t look protective.
That’s a good point, but remember, there’s a small amount of sweat, not enough to cause a large burn, and it evaporates slowly, as the heat transfer is from wood, a poor conductor, so in essence, it acts the way sweat normally does: By creating both natural convection and absorbing heat to initiate a phase change.
It’s kind of debatable whether such a small amount of fluid should cause an great energy loss though. As an engineering student, I’m inclined to ignore it, it’s more likely to simply improve on the other, more significant effects.
The problem with sweaty feet is that coal may stick to them.
Tony Robbins is selling no more than a “get rich quick” scheme. He’s getting rich really quick.
Another aspect that helps these types of big name “self help” gurus be so popular,is charging a lot of money for the “experiences”.
Studies have shown that investing a lot in something causes you to have to justify the cost after the fact to reduce cognitive dissonance.
You are more likely to sing the praises of a Tony Robbins rather than say “Well that was a total waste of money! (I got burned???)” if you’ve paid through the nose for it.
With respect, I think you might be coming down a little harshly on Tony Robbins. (Granted, people were hurt and he needs to take responsibility for that, but from what I understand he has been doing this exercise at seminars for upwards of 20 years, so my guess is that something was wrong with the conditions this time.)
I gather from those who have been to these events that the fire walk is supposed to be an exercise in breaking through fear and changing your thoughts about what is possible. To the best of my knowledge, the firewalk itself is not billed as a miracle. Thinking about “cool moss” is just a way to control your mental focus so that you don’t leap out of the coals howling at the first tickle of heat (which is what most of us would instinctively do).
Further, while I have not personally been to any of his events, I do own several of Tony Robbins’ programs and — at least in my limited personal experience — they are considerably more than “ramblings” and “easy answers.” Most of what he teaches isn’t easy, but it is effective if you are disciplined enough to apply it. As a skeptic first and foremost, it does rankle me a bit when he goes off on the occasional tangent about spirituality, and he has definitely promoted some wacky ideas about nutrition over the years. But if you are looking to re-train your brain, get control over your emotions/behavior, and eliminate self-defeating habits and thought patterns, I think there’s some really good stuff in there.
I never trust gurus who use the verb “unleash.” They are exploiting the secret suspicion most of us hold that we are bursting with untapped talent of some kind. We want to believe that all we require is to locate the lever that opens the floodgates and pull it. No need to identify the specific skills we need; no need for long sessions of painstaking study and practice. All we have to do is cast aside our fears and inhibitions, and our innate awesomeness will spontaneously gush forth.
Weird,reading this caused me to have to sprint to the bathroom.
Good one, tmac!
Obviously their belief wasn’t strong enough to overcome Nature – they need more Tony Robbins inspiration. Hand over more money please. I hope they have enough sense to sue and win – they can potentially make much more out of this than they originally paid.
I immediately emailed a news article about this to a physics teacher whose class I just attended. As noted here, he had used firewalking to discuss conduction. During class he said that wet feet would definitely be bad for firewalkers. He also talked about the ash being just right.
It’s amazing what people are willing to pay for something like this.
I was curious to see what the attendees might have paid for this event, but could only find on the Tony Robbins website the pricing on an upcoming event the first weekend of November this year in Orlando.
Standard pricing ranges from the basic of $995 (includes the firewalk and “course materials”) all the way to $2595 (includes seating in the front 3 rows)! That said, they are offering a $600 discount on some tickets, so order now ;)
Assuming that there were 6000 people at the event and that they all bought the base tickets full price, Tony Robbins’ group would be looking at generating at least $6 million in revenue! After factoring in costs, I imagine they are still making a boatload from this, and this is only from one event!
Maybe one day I’ll have an opportunity to borrow one of those expensive instruments I’ve built and collaborate on testing some ideas about firewalking. Basically, using the technology found in the infrared imagers which are now fairly common in big fire departments but with a more rigorous analysis of data rather than the default (and pretty inaccurate) temperature readout of off-the-shelf devices, we can get a pretty good idea of how much the surface of the skin actually changes temperature during a fire walk. There are quite a few variables to control for so it’s not such a straightforward thing to do if you want definitive results.
I’m betting that the ash on the coals is one of the most important things – aside from being a fairly poor conductor of heat, it’s also an excellent shield against the radiant energy of the embers. For a start, the infrared camera can show unambiguously that the ash-coated embers appear much cooler than their ash-free counterparts. Other things which I would like to establish are the extent of increase in temperature of the tissue surface and the temperature profile within the tissue (that last one has to be done in the lab with a substitute for the human foot).
Mythbusters did an episode on firewalking. Adam Savage burned his feet.
http://www.youtube.com/watch?v=7dgpsI1MdQI
Yes – but although the Mythbusters are frequently entertaining, as far as science goes they usually do a less-than-half-ass job. Neither my boss nor my sister can bear to watch the Mythbusters – they both insist that it is not only unscientific but may give people the wrong impression of science. My only response is that I’d always seen it as entertainment and not science.
That’s a bit harsh; I’d say they usually do a fully half-assed job – it doesn’t prove shit, but it gets in the bowlpark. That was supposed to be a toilet joke…shutting up now.
And don’t forget steam burns. I once really liked Mythbusters. Its TV and they did try, but brass drives out gold and lead drives out brass. I know they were wrong sometimes. I stopped watching it. Nothing good lasts forever, not on TV. Too bad.
All well and good, and perhaps even (mostly)true… but given the vast number and disparity of human types and character in this world, I’d guess there would be exceptions to the rule…
Perhaps a scientist would couch such information a little more carefully; ie “research indicates”, or “evidence shows” …..
I think it is a matter of having plenty of good quality charcoal (or using a good quality hardwood that will burn down to good quality charcoal). Charcoal does not burn very well unless you get a good flow of oxygen flowing through it (cite: my limited blacksmithing experience with a lever powered hand forge – it takes lot of sweat to keep enough air flowing to keep those coals glowing red).
Stick it in a pit with naturally restricted airflows, pack down the pathway very solidly and the low conductivity and the low heat capacity of the non burning layer of the relatively lightweight CHARCOAL on top will protect you. But you better pack it down so you don’t sink in, that’ll hurt. And wet feet are probably not an advantage, given the high thermal capacity of water, and the fact it has to (mostly) get to 100 C before it will evaporate off, you don’t want that lining your feet between steps.
Grey, fluffy ash however seems to hold a lot of heat, (heated air?) as anyone who has stepped into a stump hole fighting bushfires will affirm.
Water (ie, our feet) has a heat capacity of 4.18 Joules/gram/K
Graphite has a heat capacity of 0.71 Joules/gram/K
And…
Water density: 1 gram/cc
Charcoal density: 0.21 gram/cc
There is not a lot of heat held in a cubic metre of non-burning charcoal, but blowing air on/through it whilst alight will cause it to burn at temperatures which make steel soft.
Any partially burnt wood in the mix (ie still containing water) will hold a ‘helluva lot’ more heat (note unit of scientific precision).
Ironically,when I was about ten,I slipped and fell while walking on cool moss,and hurt myself pretty bad.
If you ever try firewalking, don’t think of cool moss.
Yeah,but you know how it is,once someone tells you not to think of something,you just can’t get it out of your head.It’s a slippery slope ;)
Don’t think of an Elephant.
Definitely don’t think of slippery slopes.
Several cultures have fire-walking as part of their mystic rites. Possibly the strangest is that practised in Fiji (although mainly now for tourists) where the walkers cross hot stones in a pit. The stones are heated by an enormous bonfire prior to the walk, the base of which is burning logs. These are removed before the walking begins. I can testify that the stones, even after the event, are too hot to touch, yet the walkers take their time and occasionally linger on them. There has, as far as I know, never been a satisfactory explanation as to how they are able to do this. Abstention from sex and a coconut free diet for a week before hand seems an unlikely solution :)
Did the Robbins weekend years ago in the UK. Paid around £100 (they discount pretty heavily if you push them!).
Interesting experience. The man is a great speaker/entertainer and many attendees were there for the nth time – it seems it must be addictive!
No discernable benefits though. Did the firewalk but already understood the physics so it was no big deal for me. Many others were blown away and I did not like to cast doubt, after all, as someone mentioned, a bit of serious, introspective soul-searching might be beneficial.
I don’t know, your article has a tone of glee that we have some dirt on someone who is to be hated by skeptics. I’m a true blue skeptic and I also like Tony Robbins. Sure, some of his ideas are wishful thinking and his advice on diet is mostly bullcrap, but he is always careful to say that he’s a coach not a guru and that the firewalk is only a symbolic gesture (I’d give a reference but it’s in the tapes.)
Some of us like to have someone remind us we can do better and are willing to pay for the advice if it helps us push for a better quality of life (Tony doesn’t tell us what he thinks our goals should be) and most of us are capable of picking and choosing as opposed to blind faith in everything he says.
Tony Robbins? I can’t trust anyone with a head that big. He looks like Herman Munster’s bastard love child.
I’d guess foot-sweat does play a role in getting a nice insulating coat of dust and ash to stick. But I’m sure concentration, peer-pressure, and delusion also do their bits to keep you from noticing your burns:
“Kim, a 22-year-old who didn’t want her last name used because she is still attending the event, said her two friends who did the walk seemed fine at first, but their feet started to blister about 10 minutes later.”