Saturday, December 10, 2011

Weekend post - The physics of road safety

I’m a little obsessed by road safety at the moment. This is partially because a very good friend of mine, a loving and vibrant young wife and mother, was killed a few weeks ago in a car accident. It’s also because I’m a driver. I spend up to 2 hours each weekday behind the wheel of a car, driving mainly around Gaborone. You can’t do that without spending much of the day considering matters of mental health. How did that combi driver not see me in my great big car or perhaps he just didn’t care? Why did that BX driver think it was acceptable to overtake in the face of oncoming traffic, crossing a solid white line and exceeding the speed limit? How did that person ever get a driving licence?

As well as questioning the mental health of drivers I often find myself wondering whether drivers studied any science at school. Don’t they know anything at all about physics?

Newton’s First Law of Motion says that the velocity of an object will remain constant unless a force acts upon it. The cup of tea on your desk isn’t going to move unless you pick it up. The ball you throw in the air will only change direction and speed because of air resistance and gravity. A passenger in a car will continue moving in a straight line within the car when the car hits a brick wall. If a car travelling at 60 km/h hits a solid object and suddenly stops the occupants will continue moving at 60km/h until something stops them as well. If they’re lucky it’ll be their seatbelt or an airbag that will slow them down as gradually as possible. However if they’re not stopped by something soft it’s likely to be something very hard indeed that does it. Something like the steering wheel, the windscreen or the wall the car hit after they’ve burst through the windscreen in a spray of blood and bone.

Let’s take a simple, not too scary example. Imagine a child is in the front seat of a car that’s just left your house. Let’s say it’s a perfectly average 9-year old girl who weighs 30kg. She’s not strapped in. The car is travelling slowly at only 30 km/h but collides with the back of a massive truck and stops almost instantly. Let’s say it takes a meter to come to a halt. In the 8th of a second the car takes to stop the girl becomes a flying object within the car. She’ll hit the windscreen at something close to 30 km/h with a force equivalent to a man weighing 117kg jumping on her. She’ll probably live.

The problem is that this isn’t typical. Who drives at 30 km/h? The other problem is that the amount of energy a moving object possesses is not directly related to it’s speed. The kinetic energy of an object is proportional to the square of its speed. Double the speed and you quadruple the energy. To make matters worse if you double your speed you don’t necessarily double your stopping distance. If the car driving that unrestrained little 9-year old girl hits the same truck while travelling twice as fast, at 60 km/h, it’ll probably still stop in a metre. This time she’ll hit the windscreen with a force of almost half a ton. She’ll probably die.

Let’s be completely depressing and double the speed again to 120 km/h. The same collision will hit her with a force of almost 2 tons. She won’t just die. Someone will be forced to reassemble her body so a relative can formally identify her. I know a very brave uncle who volunteered to identify the pieces of his niece’s body so his brother, the girl’s father, didn’t have to. He couldn’t bring himself to drive his car for weeks afterwards. Every time he got behind the wheel of his car he was plagued with the images from the morgue.

That’s why I lose my temper when I see loving parents driving their beautiful children to and from school each day and they allow their kids to stand up on the front passenger’s seat. I get even madder when I see an unbelted adult in that seat with a kid on their lap. You know what? It might not just be the windscreen that kills her, it’ll be your body hitting her from behind, crushing her from front and back. Could you live with the knowledge that your body, perhaps the body that brought that child into the world, is the thing that crushed her to death?

Maybe that’s what we need to teach in physics classes in schools. Instead of balls hitting each other or weights going up and down inclines we should use the idea of a little girl inside a metal box being driven by a psychopath. Maybe that’s the sort of science we need to cut down the slaughter on our roads.


For a quick summary of Newton's Laws of Motion see the Wikipedia page here. There's also a good explanation of the physics of car crashes here.

I'd like to say that I did all the maths in this piece myself but that would be lying. I did SOME of it myself but then was lazy and used the online car crash impact calculator here.

Saturday, December 03, 2011

Weekend Post - Is my laptop frying my fertility?”

The answer is almost certainly not but from the recent press coverage you can be forgiven for thinking otherwise.

The BBC published a story that was widely circulated that was headlined “Scientists question if wi-fi laptops can damage sperm”. The story reported that after being placed next to a laptop that was downloading data “sperm were less able to swim and had changes in the genetic code that they carry.”

Needless to say the headlines grew more and more scary as the story spread around the world’s media. The particularly hysterical British Daily Mail stated that “Radiation from WiFi connections can reduce sperm activity in up to a quarter of men” and the even more hysterical Huffington Post stated that “Wi-Fi Laptops 'Kill' Sperm”.

Unfortunately not all of the reports actually explained what the experiment involved and gave ment enough information on what to do with their laptops (and their laps).

The facts are a bit less scary that the excitable elements of the press suggest. To begin with this was just what the researchers called a “Prospective in vitro study”. This was just an experiment they conducted in a laboratory, “in vitro”, in glass. The experiment was actually very simple. Samples of healthy sperm were placed for four hours next to a laptop computer that was downloading data. Another set of samples was placed in an identical setting except there was no laptop downloading next to it. When they examined the samples after the four hours they discovered that the samples near the downloading laptop were less mobile and more damaged than the control group.

This was hardly real life. It’s certainly not what most men do with their sperm. Nevertheless it’s still an interesting study that it would be foolish to ignore. As the researchers say, “Further in vitro and in vivo studies are needed” to establish whether this effect is genuine. An “in vivo” study means a test in real life, in a living body. If other researchers can replicate these results an experiment with real men and laptops can be undertaken.

Until then we can be cautious. The most important thing is not to panic. The experiment these guys undertook is nothing like the normal way that men and women make babies. It’s also certainly not the way men usually offer their contribution to the baby-making process.

This was just one study, with a very small sample size, involving only 29 sperm samples and the effect was small. There is also no plausible explanation for how this effect might have been caused by the wi-fi network. The strength of a wi-fi signal is so weak that it’s unclear how it might have caused the damage. Critically wi-fi signals, like cellphone signals are non-ionizing, they simply don’t have the strength or frequency to cause damage to biological cells. They’re not like X-Rays or gamma rays that can have a massive impact on the human body. They’re not very different to sitting still while listening to the radio. The signals from your local radio station are around us all the time and nobody panics about them, do they?

However one thing that is known to affect sperm is heat. Excess heat around those parts of a man’s body can reduce fertility but the researchers in this study apparently ruled that out as an explanation. I’d find it perfectly easy to believe that repeatedly resting a laptop on your lap for a long period could effect a man’s fertility. Also sperm are fairly fragile and can quite easily be affected by a range of factors other than heat.

The BBC asked an expert, Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield, for his reaction to the study. He said that “we cannot infer from this study that because a man might use a laptop with wi-fi on his lap for more than four hours then his sperm will necessarily be damaged and he will be less fertile.” That sounds sensible to me. Let’s wait and see what further studies come up with before banning wi-fi networks from anywhere near prospective fathers.

In the meantime, if you’re a guy worried about his fertility then not keeping a hot laptop on your lap for too long is probably very good advice. More importantly it’s hardly the way to woo your partner, is it? Better still, try some romance, you’re much more likely to make a baby that way, it’s scientifically proven. Trust me.


The original story from the BBC can be seen here and the abstract of the study can be seen on the Fertility and Sterility site here.

For the more hysterical coverage see the Daily Mail here ("Working on a laptop wirelessly may hamper a man’s chances of fatherhood") and the Huffington Post here ("Wi-Fi Laptops 'Kill' Sperm").

For more reasoned coverage see The Register here and Time here.

Killer bananas

It’s a fantastic plot for a science fiction, don’t you think? “Revenge of the killer bananas!” However if you believe some people the risk is real.

Like many others I received an email a few days ago that began:

“Do not eat bananas until further notice. PNP will investigate if there is any truth in this, but rather be safe.”

The email then explained the danger posed by these homicidal fruit.
“Please don't eat bananas for the next 3 weeks. Several deliveries of bananas from Uvongo Kwa-Zulu Natal South Africa have been infected with necrotizing fasciitis, otherwise known as flesh eating bacteria. Recently this disease has decimated the monkey population in the south coast. We are now just learning that the disease has been able to graft itself to the skin of fruits in the region, most notably the banana which is one of South Africa’s largest exports. Until this finding scientists were not sure how the infection was being transmitted. It is advised not to purchase bananas for the next three weeks!!!”
The email continued to explain how the FDA hasn’t issued a warning because it fears “a nationwide panic”. It also said that if you have an infected wound and are far from medical attention “burning the flesh ahead of the infected area is advised to help slow the spread of the infection.”

Are you feeling scared yet? Or just skeptical?

To begin with there’s a minor technicality. The FDA is a US body, not South African. Then there’s the “science” part of it. Let’s be honest about one thing. You do NOT want to develop necrotizing fasciitis. It’s a horrible bacterial infection that causes massive irreversible tissue damage and often results in either amputation of the infected body part or death. If you want to see some scary pictures do a web search but don’t do this while eating. However, can you actually catch necrotizing fasciitis from the skin of a banana?

No. The Centre for Disease Control in the USA says that there “is no evidence that necrotizing fasciitis is transmitted by food. The bacteria which most commonly cause necrotizing fasciitis live in the human body. The usual route of transmission for these bacteria is from person to person.” There is also little sense in the statement about the “disease has been able to graft itself to the skin of fruits”.

This story is a hoax. In fact it’s a very old hoax. This has been circulating around the internet for at least 12 years. It was first seen in 1999 but with a slight difference. That time it mentioned Costa Rica, not South Africa but the words in the email were otherwise exactly the same.

You can rest assured that eating bananas is still safe and they’re still good for you. You’re not going to be turned into a zombie by eating them.

However, what I find just as interesting is why people continue to send these emails. I know of several people who’ve received it and a couple who forwarded it to others. I know of one person who even posted it on Facebook. I’m sure all of these people were perfectly well-meaning and genuinely felt it was important to warn their friends about a possible risk but did they really believe the story or were they so shocked and horrified that they felt it was an emergency?

Or are they perhaps just a bit more suggestible than others? A bit less naturally skeptical? Psychologists have certainly identified that there is a scale of suggestibility with some people being more prone than others to believe what they see and hear. They are much more susceptible to suggestion, particularly with things like hypnosis but I suspect they’re just as susceptible with anything new, like emails about bananas.

I sometimes think that I’ve become overly skeptical at times, automatically assuming that something is not true until it’s proven to be so, But then I remind myself that I think this is by far the safest approach to take to life. Isn’t it better to assume what scientists call the “null hypothesis”, that something is NOT true until there’s a good reason to change your mind? That certainly goes for anything you receive in your email inbox and anything that makes remarkable claims. Sa Carl Sagan said, “remarkable claims require remarkable evidence”. There’s nothing remarkable about the killer bananas story other than the fact that people believe it.


Snopes has a report of the original hoax email that referred to Costa Rica here. There are several useful links at the end of the article. The Skeptic Detective has a comprehensive piece on the hoax here.

The official Centre for Disease Control statement can be seen here and there's a very assertive statement from the Kwa-Zulu Natal Banana Association (I SO want to join!) here.

If you're feeling brave and want to learn more about necrotizing fasciltis you can see the Wikipedia page here which includes a fascinating but ghastly fact about the death of King Herod.

The full text of the email I received is as follows:
"Please don't eat bananas for the next 3 weeks

Several deliveries of bananas from Uvongo Kwa-Zulu Natal South Africa have been infected with necrotizing fasciitis, otherwise known as flesh eating bacteria. Recently this disease has decimated the monkey population in the south coast. We are now just learning that the disease has been able to graft itself to the skin of fruits in the region, most notably the banana which is one of south africa ’s largest exports. Until this finding scientists were not sure how the infection was being transmitted. It is advised not to purchase bananas for the next three weeks!!! If you have eaten a banana in the last 2-3 days and come down with a fever followed by a skin infection seek MEDICAL ATTENTION!!!The skin infection from necrotizing fasciitis is very painful and eats two to three centimeters of flesh per hour. Amputation is likely, death is possible.. If you are more than an hour from a medical center burning the flesh ahead of the infected area is advised to help slow the spread of the infection. The FDA has been reluctant to issue a country wide warning because of fear of a nationwide panic. They have secretly admitted that they feel upwards of 15,000 South Africans will be affected by this but that these are" Acceptable numbers". Please forward this to as many of people you care about as possible as we do not feel 15,000 people is an acceptable number."

Thursday, December 01, 2011

This is how statistics should be portrayed.

Saturday, November 19, 2011

Weekend Post - What do modern medicine, flu, ice cream and pirates have in common?

Here are some dangerous but factual observations.

Since the introduction of modern healthcare in Botswana more people than ever before have died of cancer. People suffer from more infectious diseases in colder seasons. The more ice cream that is consumed, the higher the number of drownings that occur. The reduction in the number of pirates (yes, I said pirates) in the world has coincided with gradually increasing global temperatures.

All of these are facts, there is overwhelming evidence to support them. But the big question is what they actually mean. Is it true that modern healthcare causes cancer? Does cold weather cause colds and flu? Does ice cream cause people to drown? Has the loss of pirates actually caused global warming? Should any of us actually do anything, should we take any lifestyle decisions based on these undeniable facts?

Of course not, but that’s where the danger lies. You only have to hear of these facts for a chill to go through you. It’s only one step further before you begin to suspect the benefits of modern medicine and science.

The real facts are simple. More people are dying of cancer since the introduction of modern, scientifically based medicine because we’re living longer. Cancer is largely a disease of older people. As we’ve done away with so many of the causes of death from the past that killed younger people like infectious disease and starvation other causes of death have stepped in to fill the void. Like cancer.

People suffer more colds and flu in the winter, not because our immune systems are weaker in the cold months or because viruses are stronger but simply because when we’re cold we stay inside much more. When we’re stuck inside our homes with our families we’re much more likely to spread infections by close-proximity coughs and sneezes.

The really good news is that ice cream doesn’t make you more likely to drown. However, both rates of drowning and consumption of ice cream are both associated with hot weather. Both are caused by something else.

One of the easiest mistakes to make when looking at the world is to assume that correlation implies causation. Because two observations are somehow related then one must have caused the other. It’s a fundamental mistake and one of many logical fallacies that people often make.

A recent example. A couple of weeks ago the BBC reported that scientists had announced in the British Medical Journal “a link” between use of the oral contraceptive pill and prostate cancer. The interesting thing is that only women take the pill and only men get prostate cancer so how can one possibly cause the other? The suggestion is that the hormone oestrogen in the contraceptive pill may be released in the urine of pill-taking women into the water supply. Men then drink the water and experience one of the side-effects of oestrogen: higher rates of cancer. The team of researchers from Canada had carefully examined various countries that used of different forms of contraception and found higher levels of prostate cancer in those countries where the pill was widely used. In countries where other forms of contraception were widespread the higher levels of cancer couldn’t be found.

However they were very careful to say that their study “has significant limitations with respect to causal inference”. In other words they are most certainly NOT saying that the pill increases the risk of prostate cancer. This was just what they call “an ecological study”. They observed a correlation between two things and said that “it must be considered hypothesis generating, and thought provoking”. This wasn’t an experiment, it was just some careful observations that make scientists want to ponder a bit and then design more detailed studies.

One problem is that it’s very difficult to design an experiment to test this. If we suspect there’s a link between oestrogen and prostate cancer we can’t just expose a group of men to oestrogen and see if they develop cancer, that would be inhumane. However it would be worth conducting animal tests and further ecological studies. For instance, does the rate of prostate cancer go down in countries where the use of the pill declines or where lower oestrogen pills are used?

Finally, in case you were worried, nobody really believes there’s a relationship between the number of pirates and global warming. However if you’re willing to suspend your skeptical faculties you can join the Church of the Flying Spaghetti Monster for whom this is a core belief. Perhaps not entirely seriously!


For various sources on "Correlation Does Not Imply Causation" see the Skeptics Dictionary chapter here (180kb pdf download) or the Wikipedia page here. There's also a comprehensive list of the many logical fallacies courtesy of the Skeptic's Guide to the Universe here.

The story from the BBC about the pill and prostate cancer can be seen here and the original article in the British Medical Journal here.

For the Church of the Flying Spaghetti Monster just say "Arrrgh".

Monday, November 14, 2011

Weekend Post - We're still alive!

The world narrowly avoided destruction yet again last week.

Asteroid 2005 YU55 sped past the earth at nearly 50,000 km/h coming so close that it was within the orbit of the Moon. Although this wasn’t the biggest of objects flying through space it was big enough. Astronomers estimate it was about 400m wide, roughly spherical and something that size hitting the Earth would have caused devastation. I’m no expert but a little maths suggests that it might easily have a mass of many millions of tonnes and people have estimated that impact may have exceeded the effect of any atomic bomb ever constructed.

You might think that given that 70% of the Earth’s surface is covered in water it probably would have landed there and just made a bit of a splash but that might have actually been as bad or worse than hitting land. The tsunami that followed would have been devastating.

However this was never going to happen anyway. NASA and other agencies had been tracking it for long enough to know that it would sail right passed the Earth and would hardly been noticed. If the boffins at the various space agencies hadn’t spotted it we never would have known it was there.

Of course that didn’t stop the usual suspects claiming that this was the end of the world, many of them probably the same people who predicted the end of the world on October 21st. A variety of conspiracy theorists with too much time on their hands also started spreading rumours that there was a government cover-up of the impending doom. They’ve all been proved wrong by events as well as the science.

However we have to face the fact that sooner or later an asteroid like this IS going to hit us. It’s certainly happened before. Although it’s widely thought that an asteroid impact 65 million years ago killed off the dinosaurs there’s no conclusive proof that this was the case, it’s just one of various theories. However it’s a persuasive one. Such an impact would certainly have had a devastating effect on the planet, throwing up a global dust cloud that would have prevented sunlight getting through to the plants that feed the entire food chain. Geologists have found a layer in sedimentary rock all over the world that they call the K-T boundary. This layer contains massive amounts of iridium, and element found often in asteroids. Below the K-T boundary fossils of dinosaurs are found, above the layer they’re mostly absent which suggests whatever caused the increase in iridium in the atmosphere might be connected with dinosaur extinction. Another theory observes that iridium can also be found in the Earth’s core and a massive upsurge in volcanic activity might have been the cause. At the very least the impact of that and other asteroids certainly had a dramatic effect on the Earth and it’s not something anyone wants to happen again. But it will.

Incidentally, our recent fly-by visitor, Asteroid 2005 YU55, probably wasn’t actually big enough to cause an extinction event. We’d need to have a cosmic punch-up with something a lot bigger for that to happen.

The good news is that scientists at NASA reckon they’ve now detected almost all of the asteroids that pose a threat to the Earth and there is no evidence that any of them are coming close enough for us to worry. However, they’ve adopted the “hope for the best, plan for the worst” approach. A variety of techniques have been discussed for nudging any potentially threatening asteroid off course so that it gives the Earth a miss. They’ve considered atomic weapons, ion beams and even just throwing large rocks at it. Anything just to give it enough of a nudge to bypass us.

While the threat is real and the possible effect is devastating, the chance of it actually happening in our lifetime, or that of anyone we can imagine, is so vanishingly small that it’s not worth losing any sleep. Better still to spent our time and resources fighting the things that DO threaten us, like global warming, population growth or our species’ innate ability to kill itself with the slightest provocation. Those are things worth worrying about and worth paying scientists to find solutions for.


Start with a BBC story on the asteroid passing by. Also the Washington Post covered it here.

As always with astronomical news stories you should always consult Phil Plait, the Bad Astronomer. His comments on Asteroid 2005 YU55 are here. He also has a good animation from NASA JPL that shows the passage of the asteroid.

For some of the doom and conspiracy lunacy surrounding the asteroid see here and here.

The Washington Post discusses the efforts to detect all potentially risky asteroids here. For ideas on how to deflect asteroids heading our way the Wikipedia page summarises them well.

Wikipedia also has pages on asteroid impact events and the K-T boundary including some fantastic pictures of the boundary itself.

Sunday, November 06, 2011

Weekend Post - Was Einstein right all along?

In September there was a big fuss, reported all over the world, about an experiment conducted in Italy that suggested that Albert Einstein, his Special Theory of Relativity and his notion that nothing can travel faster than light might be wrong.

Almost every newspaper in the world asked “Was Einstein wrong?” The Italian scientists claimed that they had managed to force a beam of neutrinos to travel faster than the speed of light. Admittedly only very slightly faster than light, but even a little bit would have been enough. Their beam of neutrinos had travelled all the way from the CERN laboratory in Geneva, a trip of 730km, across the border into Italy and they arrived 60 billionths of a second earlier than light would have covered the same distance. Clearly something is wrong. Either one of the cornerstones of our understanding of the universe is wrong or there’s been a mistake by the scientists. My money was on the latter.

Obviously the results are interesting. Was Einstein right or wrong? It’s a big question. But I think it’s just as interesting for the public to see how science works. The researchers in Italy went public with their results and said to the entire world (in an Italian accent) “Hey, look at this, can this be right or have we made a mistake?”

The physics community around the world went into overdrive. They thought about repeating the experiment, tried to think of new rules of physics and, most critically, tried to help the Italians discover any mistakes.

It didn’t take long for things to happen. As we speak they’re trying to repeat the experiment in a slightly different way to rule out any systematic errors in their measurements. Just as importantly experts at the University of Groningen in the Netherlands might have come up with an explanation.

This is where it gets complicated. Einstein’s Special Theory of Relativity is simultaneously simple and complex. At it’s simplest he just suggested two things: firstly that it doesn’t matter where you are or what you’re doing, the law of physics remain the same. That’s the easy one. The second is more complicated. It says that wherever you are and whatever you’re doing, the speed of light is always the same. That isn’t as simple as it sounds. Imagine you are the passenger in a car travelling at 50km/h and you lean out of the window and throw a ball ahead of the car at 10 km/h. The speed of the ball will be 60km/h.

But instead imagine now that you lean out of the car window and shine a beam of light from a torch ahead of you. Light travels at roughly a billion km/h. So the light will now be going at a billion plus 50 km/h? No. It still travels at a billion km/h. The speed of light in a specific medium doesn’t change. Not ever. If you travel in a spaceship at half the speed of light and shine that torch forwards the light will still just travel at a billion km/h.

The effect of this is profound. I don’t have the skill or space to explain the steps (I’ll put links on the web site) but it follows from this that as you go faster and faster some pretty strange things happen. The faster you go the greater your mass and the more energy is needed to accelerate further so that actually to get to light speed you would need infinite energy. Most importantly, the closer you get to the speed of light, the slower time itself progresses as seen by an outside observer.

That last element is the critical one for the Italian experimenters. The critics at Groningen noticed that the Italians had used GPS satellites to measure the time the neutrinos were travelling. But GPS satellites are themselves moving, nowhere near light speed but fast enough that their ability to measure time as accurately as the Italians needed was affected. The Groningen scientists did the maths and worked out that this would affect the calculations by, yes, you’ve guessed it, 60 billionths of a second.

The new experiments aren't done yet but we now have a very plausible possible explanation for the effect the Italians saw. Will they be proved right? Only time will tell.


The original news story can be seen here courtesy of the BBC. The original notice in Nature is here.

For an overview of Special Relativity see How Stuff Works or the Wikipedia page here.

For news on the repeat of the experiment see the BBC story here. For a summary of the Groningen suggestions about GPS satellites and their time dilation see here.

Saturday, November 05, 2011

Weekend Post - We’re all dying

More people are dying these days than ever before. And that’s a good thing.

There was a news story from the BBC last week entitled “Cancer cases projected to rise 45% in next two decades”. The research by Cancer Research UK projected 23 different types of cancer and concluded that the “numbers of cancers in men and women are projected to increase by 55% and 35%, respectively”. The impact on the health sector in the UK is going to be profound. The UK has rapidly increasing health care costs, just like we do, and the costs of care for cancer are amongst the highest. Such a dramatic increase in the number of cancer cases is going to have an enormous impact on everyone. While the story was specific to the United Kingdom, I don’t think there’s any reason to suspect we’re very different.

I’m prepared to stick my head above the parapet and make a dangerous prediction. More people reading this will die of cancer than did in their parent’s generation. In fact I’ll go further. I predict that a larger number of people will die in the next century than died in the last one. Many more.

The first reason for this prediction of doom is simple. More people will die because more people will be alive. Whether we like it or not, everyone who is alive will, one day, be dead and a greater number of living people means that eventually there will be a greater number of deaths. That’s just a sign of progress.

The fact that there are more living people is a direct result of many influences including better health care, lower infant mortality and better education. Despite what certain “alternative” health product manufacturers with a vested interest in selling their bogus products will tell you, our diet these days is much better than it was in our grandparent’s time. Our food is more hygienically produced, more nutritious and even tastes better than it did in the past. Our health care systems, while still imperfect, are an immense improvement over what existed in the past. While “traditional” knowledge systems had something to offer us, the truth is that they are nothing compared with what a pharmacy can give you today. Better transportation means that doctors and nurses are more available to us than ever before, even in a country as large as ours and with a population as small and as widely distributed.

In Botswana even with the extra burden of HIV/AIDS our life expectancy is improving. Our nation’s life expectancy at birth, even including our brothers and sisters with HIV, is now double what it was a few years ago thanks to anti-retroviral drugs and PMTCT. Our population now apparently exceeds 2 million, up by almost a quarter in a decade.

So because of all these dramatic improvement more people are alive and as a result more will die.

The second reason for growing levels of cancer is due to that longer lifespan. As a result of living longer and of all this progress we’re now dying of different diseases and conditions that afflicted us in the past. We’ve completely eradicated diseases like smallpox and can prevent many other diseases like polio and influenza and consequently most of us are living through our youth and middle age into our elderly years when we’re susceptible to an entirely different set of diseases. Most of us are now dying of diseases of the elderly, not of the young.

Cancer is a good example. The vast majority of cancer victims develop cancer in their 50s or later. If people don’t survive until their 50s they’re not going to get cancer at all. All you have to do is increase life expectancy from 50 to 60 and you’ll see a massive increase in cancer rates. It’s the downside of living longer but you have to ask yourself something. Knowing that you’re certainly going to die one day, would you rather do it tomorrow or in 10 years? Or in 20 or 30 years time? The effect of scientific and medical progress is that you and I will hopefully live long enough to die of something our great grandparents had never even heard of. What better example can there be of progress?


The original BBC story can be seen here and the Cancer Research UK paper in the British Journal of Cancer it's based on is here. Cancer Research UK also provide historical data on levels of cancer over time and by age here.

Loads of fascinating data on life expectancy in Botswana can be seen here.

Saturday, October 29, 2011

Weekend Post - A malaria vaccine?

Is it possible that we might one day live in a world without malaria? Nobody knows but we’re now a step closer.

Last week it was announced that following an 18-month clinical trial involving 15,000 African children an experimental vaccine appears to reduce the risk of contracting malaria by half. That’s not a cure but it’s an excellent start.

The potential benefit is enormous. Every year perhaps a million people around the world die from malaria, most of them African children. Anything we can do to reduce that death toll must be worth the effort. Even if we only halve the number of victims that’s half a million survivors.

This vaccine works by stopping the spread and multiplication of the malaria parasite after the victim has been bitten, by stimulating the body’s immune response and preventing it from getting a foothold in the liver.

The vaccine was based on a quarter of a century’s research by a GlaxoSmithKline team led by a research scientist called Joe Cohen. This is the stuff that Nobel Prizes are made of. A career’s research devoted to something that is so overwhelmingly good, that has such potential benefit for humanity and that can possibly save millions of lives.

I can’t help but wonder how certain people are going to react when they learn that this research was undertaken by a drug company. Not a high-brow academic in a university but an employee of GlaxoSmithKline, a company that some people will have you believe is the corporate Anti-Christ. I’m no defender of the pharmaceutical industry, they’ve certainly got a stained record but that doesn’t mean everything they do is wrong. This is a great example of how an absolute and uncomplicated good thing can come from an industry we’re free to criticise and condemn. Every so often though we have to give them some serious gratitude.

It’s happened before of course. One of the least known but most important statements ever made in human history was when the World Health Organisation declared in 1980 that “the world and its peoples have won freedom from smallpox”. A massive, worldwide campaign of vaccination and infection control over several decades eventually removed smallpox from the face of the planet. This disease killed hundreds of millions of people and it’s eradication is perhaps the greatest, practical contributions to humanity that science has ever offered. If you ever encounter one of those deluded scaremongers who say that vaccination is dangerous you need only say the word “Smallpox” and you’ve won.

One of the most disappointing things I’ve seen over the last few decades is the anti-vaccination movement. I have no hesitation in calling them either deluded or liars and some of them are both. Children have DIED because of the drops in vaccination rates around the world. Not just in the Western World where measles reappeared but here in Botswana where certain groups took what is politely referred to as a “faith position” against vaccinations. It’s not just their children we should feel sorry for it’s the rest of the community as well. One of the key objectives in fighting communicable disease is “herd” or “community immunity”. A disease like measles can’t spread as easily if most of the population are immune to it. “Chains of infection” can’t form if there are only very few people with no immunity. The more people there are who haven’t developed, or been given, immunity by vaccination the more likely the few who haven’t are to get the disease.

Malaria is different though, it’s not passed from human to human and eradicating malaria will require a different approach. However, a vaccination to give people immunity would be such an amazing step forward. The vaccine isn’t going to be with us very soon either. Scientists have earned the hard way that these things can’t be rushed. However the researchers hope that it’ll hopefully be available by 2015. Then we can really celebrate.


For a summary of the research see the Reuters story here. There's a comprehensive description of malaria from the Center for Disease Control here.

For some background on smallpox and why it's eradication is a reason for celebration see the Wikipedia page and the various links it offers. Anti-vaccination campaigners should be forced to look at the pictures of smallpox victims and imagine they show their children. For a scathing description of the loathsome anti-vaccination movement see the Skeptics Dictionary article here.

Saturday, October 22, 2011

Weekend Post - Science is critical

Please forgive the wordplay but science really IS “critical”. I believe it’s critical, in the sense that it’s vitally important, because it saves, prolongs and improves our lives. If it hadn’t been for science we’d still live to our 30s if we were lucky and most of us over the age of 40 would be in constant pain and probably wishing we were dead. We have the benefit of modern technology that allows us to communicate better than ever before, educate ourselves and entertain ourselves in a way that our grandparents could never have imagined. Actually, let me correct that. My grandmother CAN imagine it, she’s still alive and kicking at the age of 93, thanks to the benefits of science and medicine.

Science is also critical in another sense. It’s critical because it criticises. Not in a negative, whining sense, but in the best sense of the word. Criticism is about weighing the good and the bad aspects of something and science is best at that.

Unfortunately there are just too many areas of falsehood where science is needed to dispel lies and deceit.

Homeopathy is a good example. Despite there being absolutely no evidence whatsoever that it does anything, many people still swear by it. Can they all be wrong? Yes, they most certainly can. To begin with it’s simply not plausible. Homeopathic remedies are based on two simple ideas. Firstly there’s the idea that a dose of something that causes similar symptoms to a disease will cure that disease. This makes no sense whatsoever and is simply not true. Then there’s the second, even less plausible idea, that by repeatedly diluting the “remedy” the effect of the remedy actually becomes stronger.

The biggest problem homeopaths face is explaining quite how much they dilute the remedy. They typically begin by diluting the original remedy to one hundredth of it’s strength in water. Then that diluted amount will again be diluted to one hundredth so that only one ten thousandth of the original strength remains. Then again and again it will be diluted to one hundredth of each diluted strength, sometimes up to 60 times. Please don’t try to do the maths, your calculator can’t cope with numbers that big but others have worked out that many homeopathic remedies are so diluted that not a single atom of the original substance remains in the “remedy” you buy. Not one.

The homeopathic industry, when these facts became clear, suggested instead that somehow the water has a “memory” of the substance it originally contained. In 1997 a French researcher, Jean Benveniste actually published a paper in the respected science journal Nature, suggesting that water could indeed do this. That would have been fine if his research hadn’t later been shown to be fatally flawed, used biased researchers and having discarded the results that weren’t what they wanted to see. So we can forget that.

In fact, and this bit IS science, there are circumstances in which liquid water can retain certain structures and forms. Water molecules can form temporary bonds but these last no more than (take a deep breath) fifty femtoseconds which is fifty quadrillionths of a second. That’s a millionth of a billionth of a second. Even if there was any truth to this silliness no “memory” of a useless homeopathic remedy would last until the pills are in the store’s shelves.

Because of all this catastrophic implausibility homeopathy remedies don’t even need to be tested to say that they’re worthless but the scientific method isn’t as careless as that. Homeopathic “remedies” HAVE been tested many, many times and guess what? Not one of them works. Of course people THINK they work but what’s working is the placebo effect, the slight feeling of being better you get by doing something, perhaps anything.

The problem with homeopathic or any other so-called complimentary remedies isn’t that they do nothing. The problem is that they are often taken instead of medicines that DO actually do something. In the UK recently there was a major scandal because some homeopaths were recommending their silly products as preventing malaria to travellers to places like Botswana. Someone could have died. Who knows, perhaps someone did.

Science has two main roles. To give the world new ideas based on evidence and research but also to help us cast aside those ideas that don’t work any more, and probably never did. We’ve given up the belief that the Earth is the center of the universe and that your star sign predicts your future. It’s the same for homeopathy. It’s long past the time when that sort of superstition should be put aside and replaced with something that does actually work.


For a summary of homeopathy you should start with the Wikipedia entry here.

If you want a good summary of it's logical, scientific and common sense failings see the Skeptic's Dictionary entry here. There's also an excellent summary of the whole "memory of water" claptrap by Steven Novella here.

Sunday, October 16, 2011

Faster than light? No.

It looks like the the scientists in Italy who thought they found neutrinos travelling faster than light might have made a mistake. The irony is that the theory they thought they might have undermined actually explains the effect they saw.

Speedy neutrino mystery likely solved, relativity safe after all

Saturday, October 15, 2011

Weekend Post - Healthier than ever

A few months I was parking my car at my kid’s school. A young guy approached me as I left the car and asked if he could talk with me. I had a few minutes to spare and he seemed polite. I didn’t think he was going to mug me, I suspected he was trying to sell something.

He asked whether I was worried about my children’s diet. I told him that I wasn’t particularly worried which seemed to surprise him. I told him that I thought my kids have a fairly healthy diet. They probably get through a few too many chips but they’re just as likely to be found munching an apple. Ignoring this he started a lecture on the evils of “processed” and “convenience” food. His claim was that the chemicals, additives and junk in all this evil food was causing global ill-health and premature death. He suggested that if we eat organic, healthier food (and buy his pointless herbal concoctions) these problems would go away. He asked me why I think people lived longer in the past than they do now?

For a moment my brain stopped working and I stood there speechless. Was he serious? Did he really believe that in the past people were healthier than we are today?

He was, of course, comprehensively, completely and utterly wrong. We are the most fortunate group of people that has ever lived. No population is as lucky as we are today. No population in the history of the world has lived as long as we do or been as healthy.

Yes, I mean even in Botswana. I’m not just talking about places like Japan, Iceland and Australia where people seem to go on and on, I mean here too. Despite what we heard a few years ago, when the impact of HIV and AIDS was the centre of our attention, as a nation we have achieved a staggering amount.

Look at the facts. According to the figures, a baby born in Botswana in 2004 was expected to live, on average and if the mortality rate stayed the same as that in 2004 throughout his or her life, to the age of 31. Babies born now can be expected, if our much reduced mortality rate remains the same as it is now, almost to 60. And that’s the life expectancy at birth. If a kid survives the first few years of it’s life it can be expected to last a lot longer than 60.

Of course I’m not denying that HIV will continue to have an impact. However the success of anti-retroviral drugs is plain to see. We probably all know someone who we’ve seen close to the end but who is now thriving and enjoying life to the full because of the medication they’ve taking.

Perhaps my favourite statistic about the benefits of medicine involves our success with the Prevention of Mother-To-Child Transmission program. Normally a HIV+ pregnant mother has roughly a 40% risk of passing HIV to her child during childbirth. After PMTCT the risk dropped to lower than 4% and it’s dropped even further subsequently. Science and medicine did that.

So ARVs are extending the lifespan of our HIV+ siblings but what about diet? Wasn’t my car park friend right about the poisons and toxins in our food? No, he was wrong about that as well.

There is, sit down before you read this, no scientific evidence that food produced in traditional ways is any better for you than food produced using “artificial” fertilisers and pesticides. None whatsoever. In fact there is a lot of evidence that conventional fertilisers pose a very significant risk to human health. That’s not surprising when you think about it. Do you really want traces of raw cow poo on your fruit and vegetables?

There isn’t much evidence that the reverse is true either. Food produced using modern techniques is no better or worse for you than the traditional methods but one thing HAS changed massively. Food is now produced much more efficiently. The world’s population has almost reached 7 billion and we’re still producing food to feed everyone. Of course there are problems with getting it to the right people at the right time but that’s always been the case.

So here’s my suggestion for the week. Rather than pretending there was a distant age when things were better let’s look back and remember the massive proportion of children that never made it to their 5th birthday, the number of people who died of horrible diseases in their 20s and 30s and the endless sequence of famines. Let’s remember that in ancient Rome life expectancy was less than 30 and it didn’t get much better until the beginning of the 20th century.

Let’s also remember what helped us achieve all of. Science and medicine.


For a comparison of life expectancy data from around the world Wikipedia is a good starting point. It's also worth understanding what "life expectancy" actually means as well.

For details of Botswana's current life expectancy figures see here for data from the CIA World Factbook. Take a look also at the graph for death rate.

For a story on the impact of PMTCT see here.

A starting point for thinking about organic food is the Skeptoid podcast, in particular the episode on organic food here. This is where I found this piece from the American Council on Science and Health. Not worried about poo on your food? The US Food and Drug Administration are.

And that figure of 7 billion people? We'll get there later this month.

Saturday, October 08, 2011

Weekend Post - Faster than light?

There might be a revolution in science any moment now. Or maybe not.

A few weeks ago Italian scientists said that they thought they’d broken one of the fundamental laws of nature. They claimed that they had managed to force a beam of particles to travel faster than the speed of light. Admittedly only very slightly faster than light, but even a little bit would have been enough. Their beam of neutrinos had travelled all the way from the CERN laboratory in Geneva, a trip of 730km, across the border into Italy and they arrived 60 billionths of a second earlier than light would have covered the same distance. If this is true, if something really can travel faster than light, faster than 300,000 kilometers per second, then our understanding of the universe has been incomplete. After the results were announced the international media was full of headlines asking "Was Einstein wrong?"

If true, this won’t be the first time that a revolution like this has occurred in science. When Einstein first proposed his laws of relativity there was an enormous backlash against them because they contradicted the theories of Isaac Newton and the scientific establishment of the time couldn’t accept that. However, a few experiments later it was found that Einstein was right and that Newton was out-dated. Of course that doesn’t mean Newton’s theories and equations aren’t relevant, they still are in almost all circumstances. Engineers building bridges, scientists launching spacecraft, even soldiers firing guns all use Newton’s laws and they work just fine for them. It’s only in extreme circumstances that Newton’s laws stop working and Einstein’s have to be used instead.

What might have happened in Italy is something similar. Nobody is actually saying that Einstein’s theories were wrong, it’s just that they might have been only 99% correct, they might not explain everything, there might be things that his theories don’t predict or explain.

Or, and this is much more likely, the results from Italy might just be wrong. To their credit the Italian scientists have published their results and have given the international scientific community the opportunity to tear them to pieces. That’s the way the scientific process works. You have an idea, you test it, you publish your results and your colleagues do their best to find a flaw in what you’ve done. It’s not a competition, it’s just a rigorous way of testing ideas. Unlike supernatural belief systems, criticism and testing are welcomed as ways to get closer to the truth.

One of the least well understood aspects of the scientific method is that there’s a difference between facts and explanations. Gravity, for instance, is a fact. If you’re unsure, feel free to lean too far out of a top floor window and in the next few seconds you’ll be convinced. Similarly evolution is a fact. It’s been seen in a variety of quickly reproducing animals over several generations. It can be seen in fruit flies, moths and fish. These aren’t denied by anyone who has seen the facts. They don’t need any more proof. Things fall to the ground, planets are attracted to stars, animals gradually change their form to adapt to their environment over time.

What’s differs are the possible explanations. With gravity, Newton just proposed that there was an attraction between bodies but he couldn’t explain how that might happen, he just came up with rather wonderful equations to explain and predict it. But those ideas later turned out to be very slightly imperfect. That’s when Einstein came along with the idea that the structure of space and time was curved by matter. That was a better explanation of everything and filled the gaps in Newton’s explanation. A step forward. Likewise with evolution. Initially we were told that species didn’t naturally change, they were static. Then biologists began to notice what they called “speciation”, that what once identical species seemed to have changed their form to adapt to different environments. Everyone who’s seen the evidence agrees that species adapt over time, the evidence for that is clear. Then Darwin came along with his explanation, natural selection. So far, that’s the best explanation we have for the variety and adaptation of species, humans included. Maybe one day another scientist will come up with an improved explanation. So far there doesn’t seem to be a need, Darwin’s theory appears to be holding out perfectly well, just like Einstein’s.

That’s the wonderful thing about science. Whether the Italian results are right or wrong, scientists will be happy. If Einstein’s ideas continue to adequately explain things then we’re happy. If however, there’s something his theories can’t explain? Fantastic, the universe is even more marvelous and complex than we thought already.


There's a good summary of the experiment in Nature. You can see the reaction to this story by doing a Google search like this.

You can see a summary of Newton and his theories here and of Einstein here. The experiments by Sir Arthur Eddington that provided the first experimental support are discussed in Eddington's biography here.

For a summary of the scientific method see here. If you're feeling a bit more adventurous read this on Karl Popper and "empirical falsification" as the basis of science. Learn that and you understand it all.

For background on Darwin and natural selection as his explanation for evolution see here.

Saturday, October 01, 2011

Weekend Post - Radiation


It’s a horrible word, isn’t it? It conjures up images of the burnt victims of Hiroshima, their skin peeling, waiting for radiation sickness to kill them. More recently the nuclear disasters at Chernobyl and Fukushima in Japan brought back those images. But how dangerous were these disasters? How many people actually died as a result of both these accidents?

This is where things get difficult. It’s impossible to say with certainty with any cancer victim that a particular thing caused their cancer. However you can look at the number of deaths that’s more than might be expected. In the initial explosion at Chernobyl 25 years ago, 57 people were killed but subsequently the only noticeable effect has been a dramatic increase in the numbers of children with thyroid cancer. The good news is that thyroid cancer is easily and successfully treatable and so far only 15 people have died from thyroid cancer in the area. While that’s 15 tragic deaths too many it’s not much more than would be expected anyway. Similarly there appears to have been no increase in birth defects or other cancers. Nobody is going to say that the radiation leak was a good thing but the effect is much, much lower than everyone feared.

Regarding Fukushima it’s really too early to say but the initial number of deaths was minimal and those few deaths were nothing to do with radiation. It’s impossible to predict future deaths but the news is not nearly as bad as was suggested by the press at the time.

On the subject of the danger of nuclear power production you also have to consider the dangers of other ways of producing power. According to the American Cancer Society between 50,000 and 100,000 Americans might die each year from the pollution caused by conventional, mainly coal-based, power stations. That’s a risk we should all be worrying about.

But what about other types of radiation? Are they dangerous? Well, that depends. “Radiation” covers a number of things. Ask a scientist and you’ll discover that radiation is divided into two main categories: ionizing and non-ionizing. Ionizing radiation has enough energy to ionize, or break down atoms. It’s ionizing radiation that causes radiation burns by breaking down the atoms in skin cells. Ionizing radiation can also break down the atoms in DNA that might result in cancer. It’s this type of radiation that is often released by radioactive sources like those found in nuclear power stations. However, as we’ve found from the experience at Chernobyl the risk isn’t nearly as high as we all fear.

The other type of radiation, the non-ionizing type, typically has much less energy, not enough to actually damage any atoms it might meet. That doesn’t mean that it can’t cause damage but the types you and I are likely to encounter are almost all perfectly safe because the energy levels and frequencies are so incredibly low.

The best example of non-ionizing radiation is the one we see every day, just by opening our eyes. Visible light is all around us all the time, even at night, it’s what we use to see things. Visible light is not ionizing. It doesn’t have enough energy to break atoms. A common misunderstanding is about sunburn which people often believe is caused by the light of the sun. In fact it’s the ultra-violet light from the sun that is ionizing, that causes the burns.

What about the most controversial of all the non-ionizing radiations: the radio waves that are used to transmit cellphone calls? Let’s start with a simple fact. The radio waves used by cellphones and cellphone masts use a frequency that is 10 million times lower than the level required to ionize. Unless radiation can ionize atoms it simply can’t cause cancer. This isn’t an assumption, it’s just physics. The radio waves used by your cellphone are as safe as the radio waves used by your chosen radio station.

But what about that World Health Organization report that was published earlier this year that everyone read, the one that said there WAS a risk from cellphones and that they might cause cancer? Unfortunately their report was selectively quoted. They reported just one study that suggested such a link but the papers neglected to report the vast number of other studies that showed there was no relationship between cellphone use and cancers of the brain or central nervous system. Perhaps the most telling fact is that the global levels of such cancers hasn’t changed a bit since the world started using cellphones. In fact the only widely accepted risk from cellphone use is falling in a fountain while texting. Do a search on YouTube for “fountain texting” and see if you can stop laughing.

The lesson is not to believe what you read in newspapers. Do some research, be skeptical and just because someone says it, that doesn’t mean it’s true. And yes, that DOES go for me as well.



My initial source for this was an excellent episode entitled of the Skeptoid podcast by Brian Dunning called "Rethinking Nuclear Power" [transcript here]. It was there that I found the report from the American Cancer Society which suggests the number of deaths from fossil-fuel energy production.

For a general overview of radiation see the Wikipedia page on radiation, in particular the distinction between ionizing and non-ionizing radiation.

The WHO report on cell phone radiation effects is here and includes the following paragraph:
"A large number of studies have been performed over the last two decades to assess whether mobile phones pose a potential health risk. To date, no adverse health effects have been established as being caused by mobile phone use."
There's also a good summary of the facts on the Cancer Research UK site here. Read carefully the section on Category 2B risks (which currently includes cellphones). They describe this group as:
"a bit of a catch-all category, and includes everything from carpentry to chloroform."
For a good overview see the always useful Skeptics Dictionary. In particular see the page on electro-magnetic fields and radiation here and comments on the WHO story here.

Regarding the coverage of the cell phone mast in Mochudi that was destroyed by an outbreak of mass hysteria see the Mmegi story here. See also the appearance of the charlatan called Barrie Trower here. Barrie Trower is not all that he seems.

To see what can happen when you text while walking click here but remember that if you laugh at someone else's misfortune you're a bad person.


In the printed version of this article I referred to the American Cancer "Association", not Society.

Thursday, July 28, 2011

The critical consumer

Are you critical?

It’s one of my favourite words because it has two important meanings. Critical can mean “crucial” and “essential” and we all know that consumer are both of those things to a business. Well, WE know that but not all businesses seem to have realised this.

An example. We had a complaint recently from a small start-up company that engaged a web design company to construct their web site. P3,000 later no usable site existed, they were making silly excuses about their failures and then they went silent. Clearly they don’t want to make a success of their business. They seem to have forgotten the critical thing, their customer.

Another company was engaged to repair a consumer’s stereo system in July 2009, two full years ago. During this, probably the world’s longest repair period, the store confessed that they lost some of the components and weren’t capable of fixing it. They offered to replace the device at their cost and then offered cash instead. Since then it’s just been excuses. Another critical consumer ignored.

I’m sure I don’t need to remind you that the biggest culprits in the Forget What’s Critical League of Infamy are the monopolistic parastatals. Our power provider seems, despite the efforts of some of their staff, to have absolutely no idea that consumers matter. Despite their manifest and scandalous failures in ensuring power supply they still seem to operate as if we’re the ones who should apologise to them when things go wrong.

The only one of the parastatals that I think have shown any improvement in recent years is BTC but that’s only because they’ve had to confront some competition from Mascom and Orange. They’ve been forced to get off their backsides and do something to keep us making phone calls with BTC phones.

Meanwhile I still think it’s disgraceful that we pay a small fortune for unbelievably slow internet connections in Botswana, most of which are controlled by BTC in one way or another. My mother, who has the misfortune to live in the UK, has an internet connection at home that is 32 times faster than mine here. I pay P399 a month for mine, hers is entirely free, provided by her telecoms supplier with her phone line. If we, as a nation, really want to attract companies to work from our business parks and innovation hubs then we need to provide them with power and internet connections that don’t make us look like a third-world nation. Which, in case you’ve forgotten, we’re not.

My dictionary says that the word “critical” can also mean “involving an analysis of the merits and faults” of something. That’s the bit that’s important to you and me. I know it’s boring but until all consumers analyse the merits of the things we want to buy then we’re asking for trouble.

You can start by being extremely skeptical about any advertisement that uses the words “natural” or “organic”. Neither of these words actually mean anything useful. Cow manure is both natural and organic but that doesn’t mean you want to eat it in a pie. Just because a health product says it’s natural, that doesn’t mean it will actually DO anything for you. Just like homeopathic remedies, which are perfectly “natural” because they’re no more than water. They have precisely no active ingredients. Just like there’s no evidence that they work at all. In fact, the only thing there IS evidence about with homeopathy is that they simply don’t work. Any effect they have is no more than a placebo effect.

You should also be careful when dealing with the people inside stores who are trying to sell you things. Remember that almost certainly they’ve been trained how to sell things. You haven’t been trained how to resist them.

Some salespeople, particularly those selling used cars will have been trained, weird though it sounds, to keep you waiting as long as possible. Once they discover you’re interested in a particular vehicle they’ll sit you down in the office and disappear. They might say they’re off to see their manager to negotiate a special discount but in reality they’re doing nothing of the sort. They’re relying on what psychologists call “self-justification”. The longer you wait, the more you will subconsciously explain to yourself that there’s a reason for it. You must really want the car.

Many furniture stores as well as car dealers will create a sense of urgency by letting you know that there’s a time limit on a special offer. “The offer is only for this weekend and will never be repeated!” Of course you do know that the offer will be there next weekend and every other weekend as well, don’t you?

One of my favourite sales tricks is when the salesperson, particularly when you’ve been a bit challenging, will ask you “What’s the one thing stopping you from buying?” Of course there isn’t ONE thing stopping you buying, there are several but the moment you answer the question you’ve played into his hands, allowing him to focus on just one objection rather than several. You’ve made the sale a bit easier for him.

Needless to say the weapons you should take when buying something expensive is are skepticism and knowledge. And assertiveness.

If the salesman asks you to wait in his office while he negotiates for you, politely say no, you’d rather come back later. When they say there’s a time-limit, call their bluff and point out that the same offer existed last weekend. Are they really going to call you a liar? If they ask what’s the one objection you have, tell them that you have five and which one do they want first?

Above all, remember that the salesperson’s nightmare is seeing you from behind. The moment you can’t get what you want, politely remark that in that case you’ll give it a miss and turn your back on them and walk out. If a good deal really exists they’ll chase you and offer it to you. If they don’t you know you didn’t want to buy from them anyway.

Tuesday, June 28, 2011

"Pastor Irene is in town". I hope she's leaving soon.

A story in Mmegi recently announced that "Pastor Irene is in town" and that "The devil is in serious trouble". The story went on to "report", as if it was a fact, that "Botswana welcomes a woman of God" "as she casts out demons from people of all ages including young children afflicted by demons and witchcraft spells". Am I the only one that objects to these fairy tales being presented as news?

The glowing report, that was written even before she had performed these so-called miracles seemed not to consider, even for a moment, if any of this silliness was actually true. Rather than deal with the details of the claims made about her abilities I'll just ask two things. Firstly, please give me the name and phone number of anyone, just one person who experienced a miracle that can be medically proven. Just one will do.

Secondly, perhaps someone can tell me what happened to Pastor Irene's prediction, made on a previous visit to Botswana in 2007 when she predicted that on 20th November 2007 God started to roll out his big plan for ending HIV and AIDS and that very soon “All children born of HIV positive mothers will be free of HIV”.

Let's get our facts straight. There genuinely HAS been a reduction in the proportion of children of HIV positive mothers who were born with HIV and that’s tremendous news. But it wasn’t religion or Irene's charlatan version of religion that did that, it was our Prevention of Mother to Child Transmission program. It was PMTCT that took the proportion of HIV positive children born to HIV positive mothers down from 40% to virtually zero. It was PMTCT backed up by rationalism, logic and medical science that did it, not Pastor Irene's supernatural money-making schemes.

Wednesday, March 30, 2011

Mmegi - End of the world or just sanity?

In response to this article in Mmegi regarding the end of the world.
I enjoyed your article in Mmegi on 28th March entitled "Is May 21 judgement day?"

I appreciated it because unlike most religious proclamations this one can actually be tested. The prediction from Harold Camping's bizarre church group is that the world will end in the period "from May 21 to October 21 2011". They state that we will "experience great torment, which will begin with a great earthquake that opens all the graves and brings normal daily earthly life to a halt".

That shouldn't be too difficult to test.

I'm not worried though. Harold Camping is famous for having previously predicted that the end of the world would occur in 1994. Maybe I missed it? He's just one of many doomsday predictors who have persuaded their gullible followers that they have some mathematical formula for predicting the end. Charles Wesley, who founded the Methodists, predicted it would occur in 1794, 1874 was one of the many predictions made by the Jehovah's Witnesses, 1988, '98 and '99 were very popular years for various groups, even Isaac Newton predicted that 2000 would be the end. It seems that no year passes without some fringe group predicting the end of the world.

All of them have been wrong so far. Why should we think he will be right this time?

The drinks are on me in November when we can all ask Camping how he got it wrong yet again

Tuesday, March 08, 2011

Evolution is as true as gravity

In response to a very uninformed letter to Mmegi, entitled "We have never been gorillas".


Your correspondent, Shine Namane, who wrote a letter last Friday entitled "We have never been gorillas" doesn't seem to understand anything about evolution.

To begin with he suggests that evolution has taught us that human beings were "originally a gorilla or a chimpanzee". This is simply not true. Our current understanding of humanity's origins is that both humans and chimpanzees evolved from a common ancestor, another species that is now extinct. Nobody in the world believes we're descended from chimps or gorillas.

He also suggests that "christians believe that evolution is a lie". Again untrue. The Roman Catholic church accepts evolution. So do the Anglicans and Methodists. It's actually a fairly small set of fundamental biblical literalists who believe that the Bible accurately describes the origins of either the universe or life.

He also seems to overlook, or perhaps he simply hasn't seen, the vast amount of evidence for evolution. Museums around the world are stocked with transitional fossils, the DNA evidence is overwhelming and evolution can even be seen to happen in certain species that conveniently reproduce very quickly.

Mmegi readers shouldn't infer from Mr Namane's letter that there is any real intellectual and academic opposition to evolution. Darwin's theory of natural selection is as respected as Newton's theory of gravity or Einstein's theories of relativity.

Finally, far from being "degrading", "ridiculous" and "a lie", a truthful understanding of our origins can only give us a better sense of our place in nature, something that the enlightened see as magnificent, awesome and uplifting.