Thursday, January 29, 2009

Carnival of the Africans #6

Where did the time go? It's Carnival time again! Woohoo!

Go take a look over at The Skeptic Detective to see the latest instalment of the Carnival of the Africans - a carnival of blogs relating science and scepticism in Africa.

Go on then!

Tuesday, January 27, 2009

The Wedding

At the Sceptics in the Pub last month, Ivan asked me whatever happened in my search to find a secular marriage officer. So I thought it might be a good idea to do a follow-up post.

As regular readers will know (and new readers can quickly find out) in September 2008, Hide and I got married.

One of my duties in planning the wedding was to try and track down a marriage officer. This was no mean feat. Neither of us are religious, so we wanted to keep religion out of the ceremony. The problem was that in South Africa, you need to be either a magistrate or a member of the clergy of a state-recognised religion in order to perform weddings.

I was hoping to find a former clergyman who had apostatised or something, but those were near impossible to find too. So eventually we settled on a Christian pastor, Conrad Kruger, who was prepared to perform what he referred to as a "civil" ceremony.

We basically wrote a script for him, which he recited more-or-less correctly for the ceremony. We based the script on a "traditional" one we found online, and basically stripped out and reworded the religious references. If you like, you can read it here.

If you're keen to see the wedding photos, check them out here.

Back to Basics: Homeopathy

I've touched on the idea of homeopathy several times in the past, but I thought it might be a good idea to go through a quick description of what it is and why it doesn't work.

What is it?

Homeopathy is an alternative theraputic modality. It was invented by a man named Samuel Hahnemann in the late 18th century, when mainstream medical technology still included things like leeches, bloodletting and trepanning. Hygiene hadn't been invented yet, and imbalances in the Four Humours were thought to be the cause of disease.

At that time, a patient undergoing medical treatment was more likely to die from secondary infections and and side effects from treatment than to recover, so Hahnemann created what he believed to be a gentler alternative: Homeopathy.

Homeopathy is based on two main principles: Similia Similubus Curentur and Dilution. Let's look at each of those separately.

Like Cures Like

Similia Similubus Curentur (or Like Cures Like) is based on a "fight fire with fire" approach to handling disease. An idea not all that dissimilar to the use of vaccinations in modern medicine, but in a much more primitive form. It's primitive because Homeopathy employs this approach reactively and at a symptomatic level, rather than pre-emptively dealing with the cause.

The process begins with a "Proving", in which a healthy patient is given a dose of a particular substance, and is observed to see what symptoms it induces. Once the symptoms have been documented, that substance is then used to treat sick patients who demonstrate that same cluster of symptoms.

For example: caffeine would inhibit the ability to sleep in a healthy patient. So the Homeopath will treat an insomniac (who is already unable to sleep) with caffeine. Or the Homeopath might treat a patient suffering from a fever with chilli, and so on.

On the surface this seems counter intuitive. And that's exactly what it is. There is simply no known mechanism through which this might work. It's simply a ridiculous idea, and Homeopaths would need to present some pretty extraordinary evidence to prove that it works. The problem is that that evidence simply isn't forthcoming.


Somehow, Hahnemann got into his head a very strange idea: that the more you dilute a substance, the more potent it becomes. 

When we talk about dilutions in the context of Homeopathy, we're not talking about dissolving a teaspoon of sugar in a glass of water. That wouldn't be potent enough! We're talking about dilutions so great that we need superscripts to be able to write the numbers!

For instance, it's not uncommon for us to see Homeopathic remedies available at 200C. This is Homeopathic code for a dilution of 1 part active ingredient to 10^400 parts of water. (10^400 is a number with a 1 in the front and 400 zeroes behind it. I'm not going to type all that out. As far as I know, that number doesn't have a name.)

The problem comes in with a well-understood concept in both chemistry and physics called Avagadro's Constant. Avagadro's Constant tells us that once you get to a solution of 1:10^23 , you only have one molecule of the active ingredient left in the mixture.

So as soon as you get to a solution of 1:10^24, you have a one in ten chance of there being a single molecule in the mixture. 1:10^25 takes that to one in a hundred, and so on. Once you get to 1:10^400, the chances of there being even a single molecule of the active ingredient in the preparation are far too small to even consider.

So what are they selling? Pure water? Yup. Sometimes they'll dilute the substance in something other than water: alcohol or sugar pills, perhaps. But then they're simply selling pure alcohol or just plain sugar pills. In other words, Homeopathic preparations are nothing more than a placebo.

Homeopaths claim that during the dilution process, if they shake the mixture just right, the properties of the active ingredient are somehow passed into the water, through some sort of magical "water memory". If that's true, then surely the water would still hold the properties of every other substance it's ever come into contact with, wouldn't it? All the water we currently drink could just as easily be considered Homeopathic Dinosaur Urine or Homeopathic Primordial Soup. 

But Why do People Still Buy It?

This is a very good question. One that could just as easily be asked about any number of other fake medicinal preparations. The answer seems to be a little complicated.

It appears to be as a result of a cluster of known bugs in the human brain:
  • The placebo effect: since we often can't tell the difference between a sham intervention and real medicine, we sometimes feel better after taking a placebo.
  • Mistaken causality: the human brain is an extremely sophisticated pattern-recognition engine. It's far too easy for us to assume a causal link between two unrelated instances - the idea that A came before B, therefore A caused B.
  • Anecdotal evidence: hearing the stories of other people who felt better after taking Homeopathic remedies, we'll tend to believe them, and then confirmation bias comes into play - remembering the stories and experiences that confirm our beliefs, and ignoring or explaining away the ones that don't.
What's the Harm?

Another good question: if people feel better after taking a placebo, why not just let them take it to make themselves feel better?

In general I would agree with that. The problem comes in when people turn to Homeopathic remedies first, and don't seek proper medical care that could save their lives. There is a growing list of such such instances over at

Friday, January 23, 2009

Why do people laugh at Creationists?

An intelligent and witty series of videos dissecting a great many Creationist arguments in remarkable detail. Highly recommended!

(Be warned. This playlist includes 27 separate videos at the time of this posting, and seems to be continually growing. If you don't have the time to sit and watch them all in one go, I suggest you subscribe to Thunderf00t's channel, and work through them in more manageable serving sizes.)

Saturday, January 17, 2009

Magic Water Cures AIDS? No.

Water Magic
There's some trouble brewing in Tanzania. 

Homeopath, Jeremy Sherr, has travelled to deepest, darkest Africa in search of fertile grounds in which to perform clinical trials on the effectiveness of homeopathic preparations on HIV+ patients who are not taking anti-retrovirals.

It seems he wasn't able to get a test protocol through ethics boards in Europe (and rightly so), so he's taken his show on the road to places where he can get away with murder - quite literally.

New readers might not be aware that homeopathy is a supersitious belief that water can be magically imbued with healing properties, in defiance of too many laws of physics to mention. I've already done a pretty telling demonstration on the complete lack of eficacy of homeopathic products (although not exactly a double-blind controlled study - others have done those).

What makes it even worse is that Sherr has been documenting his efforts on his blog. And when his statements came under scrutiny, he resorted to some historical revisionism to try and cover his tracks.

This guy needs to be watched closely. Keep an eye on his blog here, and watch The Lay Scientist for a breakdown of the events so far, and undoubtedly a continuing commentary on how this will unfold in future.

Friday, January 16, 2009

Life on Mars? No.

This morning, while driving to work I spotted this headline on the side of the road. 

Something about it raised a red flag with me. It seemed too clear, too concise, too simple - and very sensationalist. But, of course, the prospect was exciting. Had data been returned from that various Mars missions that had finally turned up some kind of microbial life?

It seemed unlikely. NASA is under strict instructions not to look for life on Mars. The closest they can come is to look for the necessary conditions to support life, or maybe for indirect evidence to suggest that life may exist on Mars.

Could it be that NASA managed to find life, even without looking for it? Probably not.

I hypothesised that what was really going on here was that NASA (or one of the other space agencies or affiliated research organisations) had made another small, incremental, but possibly significant discovery that pointed towards the possiblity of life on Mars. And that The Times was blowing the whole thing out of proportion.

So I got to the office and looked up the relevant article. It confirmed my suspicions.

In fact, no-one has found life on Mars.

What they have found is pretty cool: that there appears to be a periodic upswing in the amount of atmospheric methane. This suggests that a fairly large amount of methane gas is being produced somewhere on the red planet, being belched out into the atmosphere, and then slowly oxidised over time.

The puzzling bit is the question of where this methane could be coming from. We know of two processes that produce methane in these sorts of quantities: volcanic activity and life. Since we're pretty sure that there's no volcanic activity on Mars, that leaves either life or a third explanation we haven't thought of yet.

This discovery increases the probability that there might be some sort of life on Mars, which is pretty awesome in itself. But it does not tell us that there is life on Mars!

This is what gets to me about stories like this. Some journalist has taken the facts of the story and twisted them into a sensationalist yarn designed to sell papers (or hits on the website). And it works. What it fails to do is give the reader an accurate description of what's actually going on. Anyone who read only the headline, or perhaps only the first paragraph of the article, would be left believing that we now know that there is life on Mars - which couldn't be further from the truth.

What makes this even worse is if life ever is actually discovered on Mars, the magnitude of that discovery will be substantially diminished in the public perception. When the headlines read "Life Found on Mars" for real, the average consumer will think "Big deal! They found that already before, didn't they? Stupid scientists."

While I appreciate the value of getting the general public interested in scientific topics, like the search for life on Mars, I think that misleading them like this does more harm than good.

Tuesday, January 13, 2009

Okay, so I'm on Twitter. When does the party start?

For months and months I've been hearing about how awesome Twitter is. While I can understand it's usefulness under certain circumstances, I can't imagine ever being in such circumstances.

But, because I hate being left out, I've finally decided to sign up and get a Twitter account.

So here I am! Now what?

I guess you can look me up and "follow" me. My username is owenswart

Right. So, that's good then, I suppose. Whee!