Merchants of Doubt

So the other day I was trying to convince one of my kids to stop playing video games and get studying one of the school subjects in which they aren’t doing very well. No response. So I looked at their grades so far and did my best to persuade them that if they didn’t do a remarkable job in the last few weeks of the semester that they likely would not pass the course. Again, no response. At this point I was getting more than a little irritated at the lack of action. “Why aren’t you doing anything about this?” The response I got, “You don’t know for sure that I’ll fail if I don’t study today and you can’t guarantee that I’ll pass if I do study right now.” This little logical fallacy is one that has bugged me for years. While it is true that I could not know for sure the outcome of doing homework it’s ridiculous to argue that playing video games is a better use of that time.

We see this type of fallacious reasoning all the time. Sometimes it is accidental. I know people who avoid the interstates because don’t know if there will be any construction work going on and they can’t be 100% sure that the off ramps will be open. Other people turn off all passenger side airbags because they can’t be 100% sure that theirs won’t be the one that goes off accidentally. I have even heard of one friend of mine who never wears his seat belt because he can’t be 100% sure that he won’t drive off a bridge and drown because he can’t get out of his car. All of these situations are based on an emotional response to something that had happened to them or a persuasive story they heard or saw on the news. Despite ample evidence to the contrary they still stick to that emotional assessment of risk and a desire for 100% surety.

What really bothers me is when others recognize this fact that you can never be 100% sure and exploit it for political and personal gains. Merchants of Doubt is the history of just such political exploitation of science and the public’s misunderstanding of certainty, statistics and risk.

Industry funded scientists focused on and magnified the uncertainty when dealing with the link between cancer and cigarette smoking. The implication being that since they can’t prove 100% that smoking is what gave this guy cancer then we don’t know what did. And therefore smoking is safe. Later on Industry funded scientists focused on and magnified the uncertainty when dealing with the consequences of the arms race. Then after that it was the link between industries and acid rain. Etc, etc, etc. Time and time again Industry funded experts have used the same tired script to justify their in action. What I found most surprising in this book is that time and time again it is the very same scientists pushing this uncertainty on the public, even when the topics are far afield of their area of training and expertise.

I took this book as a warnign to be skeptical anytime somebody encourages action or inaction just based on the fact that we can't be 100% certian. Do the research and weigh the risks. Sure, absolute certianty is rare, but relative certianty is much more common. I many not no for sure if I'm gonna get driven off a bridge, but I'm far more likely to get into an accident that does not involve a bridge and so I'm gonna continue to wear my seat belt. And the same goes for the other controvertial issues detailed in Merchants of Doubt.