A common warning sign of the misuse of science is trying to make the science appear conflicting and undecided (when it isn’t) by burying us in conflicting studies. Consider climate change research, for example, and internal documents found at Fox News ordering staff to cast doubt when reporting on all climate change science news.
The very cheeky Dr. T over at Thinking is Dangerous reminds us that, unfortunately, these techniques can be quite effective in confusing the public.
This is particularly true when people don’t understand how to recognize a well-designed, strong study of merit versus a poorly-designed weak one. So to help us all better understand, he presents us with his Five A’s of Empty Arguments:
1. Argument from Authority
A real favourite for the Complementary and Alternative Medicine people, like insisting that Charles Darwin was an advocate of homeopathy. Even if he was (he wasn’t), he’d have been wrong – it would add no value at all to the argument. Famous people are not infallible. Because they were very clever about one area doesn’t mean they are knowledgeable about all.
2. Argument from Anecdote
“My sister often suffered from ____ but since she started ____”
Again, a classic CAM argument. Religious ‘miracles’ are also perpetuated this way. This gives no idea as to confounding factors, people’s selective memories, story-telling mistakes, misinterpreted results, etc. Humans are terribly prone to bias, which is why the gold standard for clinical trials is a randomised, double-blind, placebo-controlled, multi-centre trial*. Also, from a statistical point of view, it may be pure chance, unless you have a handle on the numbers of people in the same position (the ‘n’ number).
3. Argument by Appeal to Emotion
British Member of Parliament Edward Leigh’s emotive nonsense in the Human Fertilisation and Embryology bill debate discussing human-animal hybrid embryos, takes some beating:
“If an embryo could talk, perhaps they would echo what Mary Shelley wrote in Frankenstein: ‘I, the miserable and the abandoned, am an abortion, to be spurned at, and kicked, and trampled on.”
Okay. The embryo can’t talk. End of argument. This is pure appeal to emotion, carries no weight of evidence, and in my view, demonstrates Mr. Leigh’s poor debating technique.
If my coffee cup could talk perhaps it would say: “I, the miserable stained cup, made to endure boiling water……” Nonsense.
4. Argument from the Alternative
This is trying to give weight to an argument by attempting to show that the alternative is not preferable. It may be a relevant point, but it doesn’t provide any evidence for what is being argued for. The textbook (and frequently trotted out) example of this is:
“There must be a God, otherwise there would be no point to life!”
Answer: why must there be a point to life, apart from you feel there should be one?
Regardless of the argument in point, arguing that the alternative is preferable is not evidence for the opposite.
5. Argument by ‘ad hominem’
Ad hominem is Latin for ‘to the man’, but its meaning in debating circles is to use (irrelevant and often untrue) character slight as a means of winning an debate.
Homeopaths like to use this one. If you take them to task about the lack of evidence that exists for their quackery, you will often be portrayed as a ‘Big Pharma shill’ with no independent thought. Again, even if it is true (it isn’t), it doesn’t change the fact that homeopathy (and many other CAM techniques) are quackery and have no solid evidence of efficacy. The person making the statement of fact has no bearing on the veracity of the fact.
Bonus! Dr. T later, in response to some clever contributions from his readers, added a couple other good examples of bad science arguments.
6. Argument from Antiquity
Many CAM-type rationales (and religious reasonings) come from the thought that “it has been done for hundreds/thousands of years”. It may well have a long history, but it may also have been wrong as well.
7. Argument by Analogy
“When steam builds up in a steam engine, it needs to be let out.
Emotions build in people just like steam builds up in steam engines. Therefore, emotions need to be let out.”
* Randomized Controlled Studies: Randomly assigns study participants into two groups: those who get the treatment (case) and those who do not (control) to look for differences between the two groups. The chance of being in either group is 50/50. It does not depend on things like how much a person needs treatment. A stronger form of this type of study is the Randomized Controlled Double-Blind Study. This form has the extra step of making sure that neither the researchers nor the study participants know who is getting the treatment or the placebo until the end of the study.
Find out more about scientific research methods at Nagging 101.
First of all, thanks for this blog, I enjoy reading what you have to say. Just thought I should point out something important – your little blurb on Randomised Controlled Studies. Your explanation about case vs control is incomplete and overly simple, and implies that clinical trials are run outside of ICH-GCP. Especially today, trials conducted for serious illness such as cancer will use the standard level of treatment (ie. a scientifically proven chemotherapy regimen) for an illness as the control – the case group (as you called it) will receive standard treatment PLUS a new medication or device to see if it adds benefit on top of the standard treatment. Furthermore, randomisation is not always 50/50 – there is in incredible amount of variables that can be considered when randomising groups, such as disease staging, age, cognitive level, number of treatment arms, etc.
“It does not depend on things like how much a person needs treatment”!?
Well that statement in blatantly disgusting. There are plenty of clinical trial sites who take on specific studies based on what the demographic they are treating needs, to provide them with free treatment that would otherwise be unavailable to them.
Your bias is disappointing, and disrespectable of all the people out there working their butts off to help the people on these trials – generalisations are dangerous.
Tam: “…Your bias is disappointing, and disrespectable…”
Hmmm, by this, I think you mean disrespectful? or not respectable? Neither of which would be an appropriate assessment for this post. I suspect your OWN bias is showing here.
“…clinical trial sites who provide them with free treatment that would otherwise be unavailable to them….”
Let’s be clear: Big Pharma is not running a charity here. Providing free treatment to poor patients is merely a byproduct of trying to get positive results published in order to boost sales.