The Skeptical Teacher

Musings of a science teacher & skeptic in an age of woo.

Archive for July, 2011

Firewalking is Just Physics, Not Mysticism

Posted by mattusmaximus on July 28, 2011

Fire is cool… well, not cool, because it’s actually pretty damned hot.  But what I mean is fire is really interesting to watch – what kid hasn’t at some point been fascinated simply staring into the depths of a campfire?  Do you know what’s more interesting?… the fact that some people actually like to walk on fire.  This in and of itself is just all-around awesome, but then some woo-meisters have to go and spoil it with a bunch of made-up New Age nonsense.  The purpose of this blog post is to show you why firewalking really works.

My skeptical physics colleague David Willey shows his stuff, sacrificing himself for science.  **THIS IS EXTREMELY DANGEROUS AND SHOULD NOT BE PERFORMED WITHOUT PROPER SUPERVISION**

And just to show you that I put my money where my mouth is, below is a video shot of me and my colleagues performing an experimental firewalk back in the summer of 1999…

We decided that we wanted to study the physics of firewalking for ourselves and made this video as a way of documenting the effect. There are (were) two basic competing, scientifically plausible ideas for why it is that firewalkers are not too damaged by the high temperatures during the walk across hot coals: low thermal conductivity and the Leidenfrost effect.

In the first hypothesis, it is the low thermal conductivity of ash, wooden coals, charcoal, or rocks that the firewalker traverses in their journey. Even though the temperatures are extremely high (on the order of 500-800 degrees Fahrenheit), the low thermal conductivity means the rate at which heat will transfer from the hot material to the walker’s feet is very slow. This is why when you check out a baking cake in the oven it is okay to touch the batter but not the metallic pan – the thermal conductivity of the cake batter is low whereas that of the metal pan is very high!

In the second hypothesis, the Leidenfrost effect protects the walker’s feet. The Leidenfrost effect is the same thing that prevents your finger from being burned when you touch a hot iron with a wet finger. The hot iron turns the spit into steam which forms a temporary insulating layer between the iron and the finger. In this argument, the sweat on the walker’s feet is what is vaporized and then protects the feet from the hot coals.

In the video we tested out these two ideas, and we found the Leidenfrost effect to be inadequate to explain the phenomenon. It is the low thermal conductivity of the coals which prevented our feet from being too damaged – I walked a total of four times, three times dry and once with very wet feet. After three dry walks my feet were fine, with only one very small blister (half the size of a pinky nail, barely visible on the video) on one foot, but during the walk with wet feet, to test out the Leidenfrost effect, I found the coals sticking to my feet… OUCH!!! That is where I got badly burned (which is apparent by the very end of the video).

One thing we found was clear: we successfully negotiated the fire bed without any appeals to New Age mysticism or supernaturalism – no prayers were muttered, no crystals stroked, and we never even bothered to measure our “chi” levels. Such appeals to woo are simply not necessary to explain what is happening here – in fact, I have a challenge: if any New Age firewalking guru wants to really convince me that they have paranormal powers, then they’ll walk barefoot across red hot METAL!

I submit that no one will ever seriously attempt such a stupid feat, and even if they did I guarantee they’ll only do it once ;)

For more information on the physics of firewalking, I suggest reading Dr. David Willey’s page at


Posted in physics denial/woo | Tagged: , , , , , , , , , , , , , , , , , , , , , , , , , , , | 2 Comments »

TAM9 “Skepticism in the Classroom” Workshop

Posted by mattusmaximus on July 27, 2011

This year at The Amaz!ng Meeting 9 in Las Vegas, I had the honor of presenting once again at the Skepticism in the Classroom workshop with my skeptical education colleagues, Michael Blanford of the JREF and Barbara Drescher of  Together we put on a workshop for about 200 people, mostly teachers, on the topic of how to incorporate skepticism and critical thinking into the classroom.

After a brief introduction from Michael, I tackled the issue from the standpoint of a high school teacher and shared some of the practical tips and tricks that I use in my classes to “sneak in” skepticism into lessons I normally teach.  I really like how my partner in the workshop, Barbara, described my contribution:

Photo credit: Dean Baird

Matt recapped the most important concepts from his piece last year and presented more of his fun and interesting demonstrations. I used to think that cognitive psychologists had all of the fun because we study the interesting ways that our brains and minds fool us and can blow those minds by showing them. However, after some thought I realized that the physics teachers I know have the coolest, scariest, ickiest, and most surprising demonstrations. They deal with the physical world and there are almost as many bizarre things in the physical world as there are in the mind.

Matt did not walk on fire or lie on a bed of nails, but he has done those things and has the video to prove it! What he did do is show the audience that getting your hands dirty can be a great way to reach minds.

Barbara then gave a very interesting lecture on the importance of trying to get students to think critically at an early age, such as in elementary school, and how to use the basics of philosophy and philosophical discussion to engage students.  I found her points to be very thought-provoking, and I am seriously considering working something like this into my own teaching if I’m able.

I could go on and on about it more, but I think it would be more useful for you to see and hear for yourself.  Below is my PowerPoint lecture from the workshop, complete with an audio recording of the workshop.  In addition, you should take a few minutes to go see Barbara’s ICBS blog post on the workshop; and while you’re at it, see this link to the resources that both Barbara and I are providing for anyone interested!


More stuff you might find useful:

TAM9 Lecture: Inquiry-Based Skepticism for the Classroom (my PowerPoint file I presented)

Audio of TAM9 Skepticism in the Classroom (Audio file embedded in PowerPoint file – about 1.5 hours long)

Posted in education, skeptical community | Tagged: , , , , , , , , , , , , , , , , , , , , , | 2 Comments »

Solution to the “Self-tying” Knot Trick from TAM9

Posted by mattusmaximus on July 24, 2011

This is the solution to the puzzle presented in my previous blog post – Self-Tying Knot Trick from TAM9  – wherein I show you how to supposedly tie a knot in a length of rope without releasing the ends. Of course, it is a trick, so watch the video carefully to see just how the trick is done. And have fun with some friends, family, or (if you’re a teacher) students with this puzzle.  It is a wonderful exercise in critical thinking!

Check out the Youtube video for the answer…

One last thing: I cannot claim credit for inventing this trick. I learned about it from Penn & Teller’s old book “Cruel Tricks for Dear Friends”, so credit should go to them :)

Posted in education, magic tricks | Tagged: , , , , , , , , , , , , , , , , , , , , , , | 1 Comment »

Texas State Board of Education Actually Votes IN FAVOR of Evolution!

Posted by mattusmaximus on July 23, 2011

In a bit of good news regarding the ongoing Texas evolution/creationism textbook battles, the pro-science side scored a major victory today!  You may recall that in recent years there has been a big conflict in Texas regarding the issue of material presenting (or not presenting) evolution in state textbooks.  This is also a national issue because the market for textbooks in Texas is so large that many publishers write their textbooks to cater to that market, and the rest of the country just has to follow along.  Well, due to the downturn in the economy, Texas didn’t purchase new textbooks (which would have likely been influenced by creationist nonsense, due to the idiocy of the previous BoEd); instead, the current BoEd has decided to purchase supplemental materials for Texas schools.  And here’s where the cause for celebration comes in: the BoEd voted today unanimously (8-0) to accept scientifically-accurate supplements!

The National Center for Science Education reports more details :)

Victory for evolution in Texas

Pop the champagne corks. The Texas Board of Education has unanimously come down on the side of evolution. In an 8-0 vote, the board today approved scientifically accurate high school biology textbook supplements from established mainstream publishers–and did not approve the creationist-backed supplements from International Databases, LLC.

“This is a huge victory for Texas students and teachers,” said Josh Rosenau, NCSE programs and policy director, who testified at the hearings this week. In his testimony, Rosenau urged the board to approve the supplements–recommended by a review panel largely composed of scientists and science educators–without amendments, and to reject International Database’s creationist submission. The board did just that, and asked for only minimal changes to the approved supplements.

In hearings yesterday, NCSE members and allies showed up in force. At least four times as many people testified in favor of the supplements as written, versus those opposing the supplements or demanding significant changes. …

This just goes to show you that if we in the skeptical and pro-science community are persistent, unite, and organize, then we can affect real, substantive change!  Who would have thought – with all of the lunacy coming out of Texas regarding evolution and education in the last few years – that we would have seen such a resounding victory (not one board member voted against these scientifically-sound supplements – NOT ONE!) on this subject?

Let’s not rest on our laurels, folks.  You can bet the creationists and their religiously fundamentalist allies won’t rest; they’ll be looking for their next opportunity to push their pseudoscientific nonsense in public schools as soon as we aren’t watching.  So stay vigilant!


Posted in creationism, education, politics | Tagged: , , , , , , , , , , , , , , , , , , , , , , , , , , , , | 1 Comment »

Vaccination Clinic at TAM9 is a Great Success!

Posted by mattusmaximus on July 20, 2011

Once again, I would like to toot my own skeptical horn :)  This past weekend at The Amaz!ng Meeting 9 a group of organizations – the Women Thinking Free Foundation, the James Randi Educational Foundation, Skepchick, and the Southern Nevada Health District – worked to bring a free vaccine clinic to the conference.  And boy did we kick all kinds of ass!  Look, I have photographic evidence…

Me and Bad Astronomer Phil Plait, kicking ass with our official Hug Me gear (T-shirts and teddy bears for sale via the WTFF)!

Photo Credit: Jamie Bernstein a.k.a. The Original Skeptical Ninja

Like the WTFF’s previous clinic at Dragon*Con last September, we offered free TDaP vaccinations for anyone who came into the clinic (TDaP stands for “tetanus, diptheria, and pertussis”) and it was also part of the WTFF’s “Hug Me, I’m Vaccinated!” campaign to reach out to the general population, and parents in particular, about the need for vaccines and how anti-vaccinationist propaganda can be deadly.

At the Dragon*Con clinic, we vaccinated over 200 people in two days, which was – according to the clinic workers – a massively successful clinic.  But we aren’t satisfied with that success, which became apparent when our clinic at TAM9 blew that record away by vaccinating a whopping 306 people in 5.5 hours!  W00t!!! :)

A lot of people came up to me during the clinic and thanked me and my skeptical colleagues at the WTFF and JREF for doing this work, but I have to say that one of the biggest reasons why we can do this at all is because of the generous support from people like you.  We want to keep doing these clinics, and we’re planning to do another one at Dragon*Con 2011 – but we cannot do it without your support.  So please consider making a donation to this worthy cause…


Thanks again for all your support – YOU kick ass! :D

Photo Credit: Jamie Bernstein a.k.a. The Original Skeptical Ninja

Posted in medical woo, skeptical community | Tagged: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , | 7 Comments »

The “Loch Ness Monster”… of Alaska?

Posted by mattusmaximus on July 19, 2011

So there’s this video going around the Internet where some fishermen claim to have discovered a new “Loch Ness Monster”… in Alaska.  Here is the article and related video wherein witnesses claim to have found evidence of the creature…

The Loch Ness Monster of Alaska?

Move over, Montauk Monster. Step aside, Nessie. There’s a new sea creature in town–maybe. Footage of a 20- to 30-foot long creature caught on tape by fishermen suggest we have an Alaska bonafide marine-creature mystery.

The black and white footage from 2009 is by no means definitive. It is taken on a rainy day with a shaky camera, which make it all the more confounding. But you can check out the testimony of people who say they witnessed the creature’s appearance in the video above.

The Alaska-dwelling creature has been labeled a “Cadborosaurus willsi,” which means “reptile” or “lizard” from Cadboro Bay, British Columbia, where it was originally spotted centuries ago. Called “Caddy” for short, it has a “long neck, a horse-like head, large eyes, and back bumps that stick out of the water,” according to a report on MSNBC. …

So “Caddy” is the newest craze to hit the cryptozoology community of “monster hunters”, it seems.  Sadly, the supposed “evidence” here is no better than the best ever provided for the Loch Ness Monster, Bigfoot, or any other of the many mythical creatures that cryptozoologists claim exist.  In this case, we have a video of very poor quality – it is out of focus, grainy, and shot under bad weather conditions.

The claims that “this cannot be a sea lion” are also very questionable, because this assumes that the “humps” appearing behind the head that surfaces are actually part of the creature’s back without any kind of confirming evidence.  But here is a more reasonable and plausible explanation: as any seafarer knows, oftentimes when a sea lion, boat, or any other waterborne craft/creature is moving across the surface of the water it produces a regular pattern of ripples, such as those shown below…

Looking at this boat and its pattern of ripples from the side at a distance can certainly make it appear like there is a series of humps breaching the water behind the boat, but that is simply an illusion.  It is my guess that this is the same kind of illusion which has fooled these fishermen into thinking they are seeing “Caddy”.

One would think that if cryptozoologists are actually serious about investigating their claims, they could come up with something better than blurry photos, crappy video footage, and a profound lack of alternative explanations which are consistent with the environment they are observing.  Color me unimpressed.

Posted in cryptozoology | Tagged: , , , , , , , , , , , , , , , , , , , , , , , | Leave a Comment »

Self-Tying Knot Trick from TAM9

Posted by mattusmaximus on July 18, 2011

Well, I’m back from The Amaz!ng Meeting 9 in Las Vegas, and I’m slowly but surely getting caught up on things.  I just wanted to take a moment to share with everyone a trick I showed off during my “Skepticism in the Classroom” lecture at TAM9.  In this video, I show how to use a simple nylon rope to perform a *seemingly* mathematically impossible feat: having the rope tie a knot in itself without releasing either end of the rope. I show this to my students as a lesson in skepticism and critical thinking, and it never ceases to catch their interest.

Can you figure out the trick? Stay tuned to my Youtube channel for the solution ;)

Posted in education, magic tricks, mathematics | Tagged: , , , , , , , , , , , , , , , , , , , , , , | 2 Comments »

The Digital Guide to The Amaz!ng Meeting 9 (via Tim Farley)

Posted by mattusmaximus on July 13, 2011

Well, The Amaz!ng Meeting 9 (the largest skeptical gathering ever!) is about to get underway in Las Vegas! I will try to provide some updates about how things are going at the conference and the general goings on, but I know that I’m only one guy with a limited perspective on things.

So, whether you are attending TAM9 or not, perhaps one of the best things to do to keep up is to read the following excellent post on the Digital Guide to TAM9. The author is Tim Farley, perhaps better known as the creator of the What’s The Harm? website, and this post gives you all the details (and I mean ALL the details) on how to follow what’s happening at TAM9…

Digital Guide to The Amaz!ng Meeting 9 (TAM9)

The purpose of this post is to be a clearinghouse for all things digital related to the meeting. I’ll show you how to get information you need about the show, how to get connected and stay connected once you are in Las Vegas, and more. I’ll provide links to a variety of resources online that will help.

Please note: in most cases I did not create the resources listed. Most were created or published by the JREF itself, other TAM9 attendees or JREF Forum users. Where possible I’ve also provided links where you can get in touch directly with the content creators. …

Posted in Uncategorized | Tagged: , , , , , , , , , , , , , , , , , , , , , , | Leave a Comment »

Vaccine Clinic at The Amaz!ng Meeting 9

Posted by mattusmaximus on July 8, 2011

As most people within the skeptical community know, next week The Amaz!ng Meeting 9 will be coming to Las Vegas.  It will probably be the biggest gathering of skeptics ever, and the lineup of speakers and workshops (one of which I’m helping to run) promises to be quite illuminating and informative.  Something else which will be taking place at TAM9 is a vaccine clinic, held in conjunction with the JREF, Skepchick, and the Women Thinking Free Foundation as part of the WTFF Hug Me, I’m Vaccinated! campaign; this will be very similar to the highly successful clinic held at Dragon*Con last year.  The clinic will be giving away free vaccinations for TDaP (tetanus, diptheria, and pertussis) to anyone who wishes to receive one – so if you’re at TAM9 and you’re not sure you have had your vaccinations updated, come on by the clinic!

In addition, even though these vaccines are free for those obtaining them, they still cost money, so we are looking for donations to help us facilitate future clinics.  If you are interested in donating to this worthy cause, click here…



And here’s more general information about the Hug Me campaign.  Who doesn’t like good health AND hugs?  What a deal…

Posted in medical woo, skeptical community | Tagged: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , | Leave a Comment »

Discovery Channel’s “The Supernaturalist” is Super Stupid

Posted by mattusmaximus on July 7, 2011

There was a time when I had really high hopes for cable channels like the Discovery Channel – I had hoped that they would be bastions that would promote sound science amidst a sea of sensationalistic cable TV docudrama and crapola (can you tell I don’t watch TV or cable?)  Sadly, the more time that passes, the more and more I shake my head in shame for what has happened to the Discovery Channel.  Case in point: the newest show on this “science” network, “The Supernaturalist”.

The show just launched a few days ago, and the Discovery Channel was promoting it as the Next Big Thing on their network.  Here’s the press release:

Mind-blowing Magic in The Supernaturalist



Dan White performs mind-blowing magic: manipulating physical objects, performing surprising card tricks and making items appear from seemingly thin air. All of this, he admits, is merely an illusion. White has a mission: to find REAL magic. In Discovery Channel’s THE SUPERNATURALIST, premiering Wednesday, June 29th at 10PM et/pt, White travels to a remote corner of the planet and finds himself in a place where magic isn’t just tricks. It is believed to be very real… and even dangerous.

Locals in the Himalayan country of Nepal believe there are monks within its borders who use their powers to harm anyone who crosses their path. White relies on his talents as an illusionist to open doors normally closed to outsiders in an attempt to find one of these feared monks and – hopefully – witness his true magic. White’s mission will introduce him to many people, each getting him one step closer to the men in the mountains.

Unfortunately, in Dan White’s quest to “find REAL magic” – and the Discovery Channel’s quest to continue catering to the lowest common denominator (remember their stupid ghost-hunting show?) – it seems that everyone involved has left their basic critical thinking skills at the door.  For example, check out this footage of when Dan White “discovers” the levitating powers of the monk he has sought for so long…

The overly credulous nature of this clip, and how Dan White – the supposed skeptic – plays it up as legitimate (honest!) is downright pathetic.  There are some very basic questions to ask regarding a scenario like this:

1. Why isn’t the filming done in one continuous shot?  Note all the breaks in the clip between the time the monk sits down and when he “levitates”.

2. Why does the monk have to sit where he does, in front of a wall full of curtains that can easily obscure a device which can lift him?

3. Why doesn’t Dan White ask the obvious question as outlined in #2 above, instead of standing there looking like an idiot with his mouth agape?

4. Why doesn’t Dan White, our token “skeptic”, take a moment to simply walk over to the side to make sure there isn’t a mechanical arm or similar contraption connecting the monk to something behind the curtain.  On a related note, why isn’t this camera angle shown?

A simple application of Occam’s Razor is all that is necessary to slice through what is very clearly a bullshit display put together to get ratings.  Folks, this is a big joke, and if anyone takes it seriously the only one’s laughing will be the executives at the Discovery Channel who are guffawing at having one over on gullible viewers.  Fortunately, there is a silver lining: I have been inspired to incorporate this footage and a critical analysis of it into my upcoming talk at The Amaz!ng Meeting 9 in Las Vegas next week – it will make a good lesson for my students :)

Posted in ghosts & paranormal, magic tricks, media woo, physics denial/woo | Tagged: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , | 44 Comments »


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