Evolution. Climate change. Vaccination.

It is difficult to deny the power of words when just a few short phrases on the internet can induce the intellectual equivalent of DEFCON1.

No need for alarm, however. I am not writingone to change any minds – and even if I tried, whatever I might say is only likely to strengthen the opinions you already held in the first place.

Even if we disagree. In fact, especially if we disagree.

Weird, right? How does that happen?

The scientific literature continues to grapple with the phenomenon of “polarizing opinions,” which are far more complex than simple disagreements. What we find with polarizing opinions is increasing divergence over time; that is, as more and more evidence is introduced, the magnitude of difference between camps actually becomes wider, not smaller. Gaps become chasms.

We can trace this behavior back to at least 1979, and the seminal work of Dr. Charles Lord.1 He looked at people on opposing sides of the death penalty, and he gave them two studies to read, one confirming and the other denying their preexisting beliefs about deterrence.

Dr. Lord found that when presented with mixed evidence on a complex issue, people tend to double-down on their initial position, arriving at opinions that are even more extreme than they were at the outset.

A surprising aspect of this phenomenon is that it is not necessarily linked to a lack of understanding. In the case of evolution, for example, Dr. Dan Kahan of Yale found that proponents or oppotwonents of evolutionary theory were equally likely to respond correctly to questions about natural selection or mutations.2

The conclusion here is that many opponents of evolution grasp the underlying concepts just fine. They just don’t buy it. And a fascinating add-on to these findings: the higher your science literacy, the more unshakable are your beliefs.

It is called biased assimilation, and it begins by acknowledging the subtle idea that belief and understanding do not necessarily correlate. Those with the highest understanding are also the most proficient at crafting a firm position, while deftly discrediting any evidence to the contrary. In short, the smarter you are, the harder it is to change your mind.

Today on the web, we find that biased assimilation is further reinforced by a variety of recommender systems. These are algorithms that link us to additional content, tailoring our consumption of information based upon past behavior, or based upon similarity to content being viewed right at that moment. The result is a comforting echo-chamber for our preconceived notions, where beliefs are seldom challenged.

As science and healthcare communicators, we must sometimes wade into the turbulent waters of scientific controversy, so an understanding of polarity triggers is an important tool. While these waters remain quite murky, a few insights have emerged.

Avoid Controlling Language: Strong words such as “must” or “cannot” are more likely to lead to a routine dismissal of your message. It is probably no surprise that this has been shown to be particularly true for communications aimed at teens and younger adults.3

Find a Surprise Validator: Individuals are more likely to consider contrary evidence if it is presented by a source that is otherwise similar to them. When a foe turns into an ally, this can serve as an integral part of the story. While Jenny McCarthy’s vacillating views on vaccination may not be the most compelling example of this, at the same time, it is one that you’ve probably heard about.

Dodge the Poisoned Well: This occurs when scientific and technical disputes are entirely overshadowed by social matters rooted in distrust. There is little hope for the success of reasoned arguments when the well has been poisoned for meaningful dialogue, and opponents are viewed as irrational, arrogant, and likely harboring a hidden agenda. Conflicting evidence may then be discarded prima facie as unreliable because the source itself is unreliable, and “expert opinion” may be deemed the least credible of all! Consider that sometimes the most valuable mediator of a story may be someone indifferent to the issue, with no vested interest whatsoever.

Create a New Story: It is difficult to fight a story with facts, so the most appropriate tool may be a new story. Calls to action, and the consequences of inaction, may serve a greater persuasive purpose than a didactic download of data, much of which opponents will have already heard and chosen to ignore in the first place. Humor can be a useful and disarming tool when crafting this new narrative.

Each of us will be guilty of biased assimilation to some extent. Consider, for example, a study on the many health benefits of chocolate. Do you view these findings through a rigorously skeptical filter, or take it pretty much at face value? Thought so.

The march of science is sure to yield new battlegrounds in the future, and understanding the complexities of communication in these potential minefields – that some opinions are forged in beliefs, not data alone – will be vital for science communicators. It is vital today, too, but remains a work in progress.

1. Lord CG, Ross L, Lepper MR. J Pers Soc Psychol. 1979;37:2098-2109.
2. Kahan DM. Advances in Political Psychology. 2014. doi: 10.1111/pops.12244.
3. Hu J. Psychol Health. 2015;30:423-440.