Biochemical Soul Musings on Nature, Science, Evolution, Biology, and Education

17Sep/08Off

Tangled Bank #114 is Live

The latest edition of the blog carnival, the Tangled Bank #114 is now up over at Science Made Cool. Go check out the latest in science blogging from the past fortnight.

They have included my own recent post on using the new Vaccine/Autism study, which further confirms the LACK of any connection whatsoever between the two, to teach science students about the "post hoc ergo propter hoc" fallacy" in pseudoscience.

"post hoc ergo propter hoc" means "after this, therefore because of it", and refers to the phenomenon where something will happen to someone, then something else will happen, and the person will erroneously conclude that the first caused the second.

An example: a child gets a vaccination, then a child develops autism, then the parent says "vaccines caused my child's autism."  This is false logic. The causation could be true, but studies would have to prove it. In the case of autism/vaccinations, this has been repeatedly falsified.

7Sep/08Off

Current Headline News Useful for Freshman College Science Courses

As I've mentioned before, I am currently teaching an intro level biology course for freshman non-majors. At the moment we're still talking about the nature of science, specifically focusing on junk science and common misconceptions and misrepresentations of science in the media and in public opinion.

One of the things I'm using is a clip of an old John Stossell report called "Junk Science: What you know that may not be so". Two examples are presented in this clip. In the first, it presents the old "breast plants caused my connective tissue disease" explosion that occurred in the last decade. Basically, a bunch of people got sick after getting breast implants and they attributed it to the implants themselves. In reality, after many many studies, we learned that the incidence of disease in people with breast plants is identical to those without them.

In a second clip, a similar thing happened with dioxin exposure. Essentially, we now know that these exposures had no effects on humans.

Both of these examples present clear cases of the phenomenon of fallacious logic referred to as "post hoc ergo propter hoc", which means "after this, therefore because of it". People got sick after the events (implants or dioxin) and attributed the incidents as the cause, mistaking a (coincidental) correlation with causation.

Both clips also show quite well how media, lawyers, fear, ignorance, and politics all have their own hands in the promotion of junk science.

In an excellent piece of news from this Friday's reports on LiveScience.com, written by Benjamin Radford, yet another study, this one considered large and definitive, has shown that there is no link between childhood MMR vaccines and autism. Most of the science community has known this for years, but as with many other examples, fear trumps sound logic and many still cling to this fear.

Excerpt:

Many parents came to believe that vaccines caused their children's autism because the symptoms of autism appeared after the child received a vaccination. On a psychological level, that assumption and connection makes sense; but on a logical level, it is a clear and common fallacy with a fancy Latin name: post hoc ergo propter hoc ("after this, therefore because of it").

Because the human mind seeks connections, people often misattribute causes, thinking that, "B happened after A did, so A must have caused B." The child was fine until he was vaccinated, and soon he showed signs of autism. It makes sense--except that it's not necessarily true. It's like saying "roosters crow before the sun rises, so the roosters must have made the sun rise."

The article presents the mistake of using individual correlations to attribute vaccinations to autism in an easily understandable way, and would make an excellent VERY short reading for any intro level science course. I like to send a steady stream of easily digestible current biological news bits to my students, especially for non-science majors. It's so much easier to keep their attention and to make them see why they should care when you can weave currently reported debates into the lesson. So if any of you are teaching such a course, I highly recommend this article for both its relevance to our lives and to understanding how misuse of "evidence" can lead to unnecessary fears and "pseudoscience".