Have you ever read a book that had been published years before you read it, but you find it strikes a chord with you as if the author was writing it for the present you're in? I just had that experience reading Carl Sagan's last book, The Demon-Haunted World: Science as a Candle in the Dark (Random House, NY).
I had not even known Sagan had written it until recently, although it was published in 1995, the year before he died. I had been enthralled by the television series "Cosmos" and the book was given to me as a Christmas gift from my parents. I still have it, tattered and well-traveled, on the shelf reserved for the favorites. Sagan's ability to communicate the wonder and challenge of science remains unequaled. Having worked as a science communicator myself for the National Pesticide Information Center, I know how difficult, and how important, communicating science to the general public can be.
The Demon-Haunted World has many prescient chapters that ring even more true today than they did sixteen years ago; I won't spoil your personal discovery. But in an election year of unparalleled hyperbole, in a time marked by highly organized, very well-funded anti-science campaigns, a few pages of this book need to be widely distributed. These pages constitute Sagan's Baloney Detection Kit.
To quote the book, "What's in the kit? Tools for skeptical thinking."
They include the ground rules that every practicing scientist should have memorized by heart. Information must be independently confirmed to be true. Authorities have no special standing, only experts do. However, the experts had better be prepared to defend their views in vigorous, open debate, which should be strongly encouraged. The validity of ideas is independent of the rank or status of the person presenting them. Scientists should maintain at least a small herd of alternative hypotheses that may explain a phenomenon to avoid unreasonable attachment to any one idea. All hypotheses need to be able to be falsified in order to be useful. If faced with two equally plausible explanations, choose the simpler of the two.
In addition, included for all of us is a list of fallacies to be recognized and called out for the bad practices they represent. Among the most relevant of these:
Confusing causation for correlation. Just because two phenomena occur together doesn't mean that one causes the other. Weight gain and baldness are both associated with aging in men. However, gaining weight does not induce baldness.
The false dichotomy (also known as the excluded middle). Either you're for something, or you're against it. If all parts of the genome haven't been shaped by evolution, then evolution isn't valid. The slippery slope is a special case of the excluded middle. Another special case is the short-term versus the long-term argument. We need the jobs mining and transporting coal will provide, so we can't afford to pay attention to future environmental or human health costs.
The non sequitur, which literally means "it doesn't follow". This is the derailing of the logical argument. For example, the claim that teaching human reproductive biology in school will lead to sexual promiscuity is a non sequitur.
Misunderstanding of statistics and probability. This is a hard one for folks without much math background, but Sagan offers an example that illustrates the extreme: President Eisenhower was purportedly alarmed to learn that fully half of all Americans were below average intelligence.
Observational selection: we consciously or unconsciously winnow our recognition of events to support our cherished viewpoints. For example, only the failures are enumerated, not the successes. Solyndra went bankrupt, so there is obviously no point in supporting companies developing alternative energy technologies. We are also prone to forgetting failures. In both cases, we're not going to be able to learn from what we've tried before if we choose not to remember it.
The straw man: the straw man is built from a gross oversimplification of a position to make it easier to attack. If global warming is actually occurring, how come it snowed so much in some places last winter? Straw men often turn up as jokes, but in this case both sides have to appreciate the caricature for the joke it is meant to be. Otherwise it isn't funny at all.
Ad hominem: Latin for "to the man", this is similar to shooting the messenger. It involves attempting to discredit the source so no one will believe them, even if there is abundant support for what they're saying. Think character assassination. Unfortunately it has become an increasingly common strategy in public discourse in general and for the climate change denialist movement in particular. Deniers are now seeking to discredit the scientists themselves, in hopes that the public will be fooled into thinking that if the scientist is a jerk, his or her work will not be worth anything.
Inconsistency: this one is miserably pervasive, which is a sad comment on all of us because it's also one of the easiest ones to spot and call out. You might also refer to this one as the pot calling the kettle black, and in the case of ethical positions, the word "hypocrisy" might apply.
Sagan points out that all tools, even a baloney detection kit, may fail or be misused. However, it still seems worth investing in developing a good one to better recognize what's being served up in the media and public discourse. In fact, maintaining a healthy, fully functioning democracy requires that all citizens be so equipped.
Sagan makes an eloquent argument for remembering what science really is: a universal pursuit whose revelations are independent of religion, nationality, language, or political persuasion. These are truths unaffected by whether or not we exist to recognize them. Science exists independently of its discoverers. It is up to us to wisely use and apply the discoveries, making sure that we all engage in open, skeptical, and reasoned debate that acknowledges the potential risks and benefits.