When in doubt, shout – why shaking someone’s beliefs turns them into stronger advocates

By Ed Yong | October 19, 2010 11:00 am

EndisnearYou don’t have to look very far for examples of people holding on to their beliefs in the face of overwhelming evidence to the contrary. Thousands still hold to the idea that vaccines cause autism, that all life was created a few thousand years ago, and even that drinking industrial bleach is a good idea. Look at comment threads across the internet and you’ll inevitably find legions of people who boldly support for these ideas in the face of any rational argument.

That might be depressing, but it’s not unexpected. In a new study, David Gal and Derek Rucker from Northwestern University have found that when people’s confidence in their beliefs is shaken, they become stronger advocates for those beliefs. The duo carried out three experiments involving issues such as animal testing, dietary preferences, and loyalty towards Macs over PCs. In each one, they subtly manipulated their subjects’ confidence and found the same thing: when faced with doubt, people shout even louder.

Gal and Rucker were inspired by a classic psychological book called When Prophecy Fails. In it, Leon Festinger and colleagues infiltrated an American cult whose leader, Dorothy Martin, convinced her followers that flying saucers would rescue them from an apocalyptic flood. Many believed her, giving up their livelihoods, possessions and loved ones in anticipation of their alien saviours. When the fated moment came and nothing happened, the group decided that their dedication had spared the Earth from destruction. In a reversal of their earlier distaste for publicity, they started to actively proselytise for their beliefs. Far from shattering their faith, the absent UFOs had turned them into zealous evangelists.

The case study inspired Festinger’s theory of “cognitive dissonance”, which describes the discomfort that people feel when they try to cope with conflicting ideas. Festinger reasoned that people will go to great lengths to reduce this conflict. Altering one’s beliefs in the face of new evidence is one solution but for Martin’s followers, this was too difficult. Their alternative was to try and muster social support for their ideas. If other people also believed, their internal conflicts would lessen.

Festinger predicted that when someone’s beliefs are challenged, they would try to raise support for those beliefs with paradoxical enthusiasm. Amazingly enough, during the intervening half-century, this prediction has never been tested in an experiment – that is, until now.

In their first experiment, Gal and Rucker asked 88 students to write about their views on animal testing for consumer goods, but only half of them were allowed to use their preferred hand. This may seem random, but previous studies have shown that people have less confidence in what they write with the hand they’re less comfortable with. Indeed, that’s what Gal and Rucker found in their study. When asked later, the volunteers who didn’t use their dominant hand were less confident in their views.

However, they were also more likely to try and persuade others of those same views. When they were asked to write something to persuade someone else about their opinions, those who felt less confident wrote significantly longer missives. With a sliver of doubt in their minds, they spent more effort in their attempts at persuasion.

Gal and Rucker also found that this extra effort vanished if the volunteers had a chance to affirm their own identity beforehand. If they were asked to identify their favourite items (books, cities, songs and so on) before writing about animal testing, the choice of hand had no effect on their advocacy attempts. If they were asked to say what their parents’ favourite things were, the hand effect reappeared.

In their second experiment with 151 fresh volunteers, Gal and Rucker found the same effect. This time, they influenced the recruits’ degree of confidence by asking half of them to relate memories where they were brimming with certainty, and the other half to describe relate memories where they were plagued with doubt Afterwards, the volunteers said whether they were vegans, vegetarians or meat-eaters, how confident they were in their opinions, and how important their choice was to them.

As expected, those who remembered times of uncertainty were less confident that their food choices were the right ones. And as before, those same doubtful volunteers advocated their beliefs more strongly. When asked to imagine convincing someone else about their diet, the uncertain group wrote significantly longer messages and spent longer composing those messages.

This experiment – with a different method of manipulating confidence, a different issue at stake, and a different measure of evangelical effort – adds weight to the results of the first one. However, the effect only held true among those who felt that their dietary preferences were important to them. This showed (perhaps, more expectedly) that the ties between doubt and advocacy are stronger for beliefs that are people hold more dearly.

The third experiment found similar results, using a far more trivial issue (well, supposedly more trivial). Gal and Rucker worked with 106 students who all thought that Macs were superiors to PCs. Again, the duo successfully manipulated the students’ confidence by asking them to remember a previous incident of certain resolve or uncertain doubt.

The students had to imagine convincing a PC-user about the merits of an Apple product but this time, half were told that they were talking to a Windows-diehard, and the others were faced with a more open-minded partner. As before, the students put more effort into persuading their imaginary partner if their own confidence was weakened, but only if their partner was receptive.

In all three cases, Gal and Zucker found that doubt turns people into stronger advocates. More subtly, their study shows that this effect is stronger if someone’s identity is threatened, if the belief is important to them, and if they think that others will listen. It all fits with a pattern of behaviour where people evangelise to strengthen their own faltering beliefs.

Their study also casts the acts of advocates in a different light. They might be outwardly trying to change the minds of other people but their actions could be equally about bolstering their own beliefs. As Gal and Zucker write:

“The present research also offers a warning to anyone on the receiving end of an advocacy attempt. Although it is natural to assume that a persistent and enthusiastic advocate of a belief is brimming with confidence, the advocacy might in fact signal that the individual is boiling over with doubt.”

Reference: Psychological Science http://dx.doi.org/10.1177/0956797610385953 or here

More interesting psychology:


Comments (46)

  1. Nemesis

    I’ve been there before.

  2. Pam D

    Ah, interesting but what about those of us who are consummate doubters?

  3. Bob Carlson

    I wonder what this says about the strategies of either the so called gnu atheists or their accommodationist opposers. And the apparent impact of some being required to use the non-preferred hand would seem to support those who argue that free will is merely an illusion.

  4. magetoo

    the so called gnu atheists

    “Stallman is a myth, wake up people!” or what?

    Interesting results. It makes a lot of sense, but I’m beginning to be uncomfortable with all the things that cognitive dissonance ties into. (Can I have my mind back please?)

  5. Lyr

    They shout loud because they’re trying to convince themselves.

  6. JMW

    Apropos of nothing, there are days when I buy for lunch what I call my “Cognitive Dissonance Special”:

    – piece of vegetarian pizza
    – piece of meat lover’s pizza
    – can of diet ginger ale

    Mwa ha ha ha ha ha!

  7. Joe

    Vaccines can’t cause autism. Autism is simply a term from the psychiatric DSM-IV manual. It’s nothing but a smokescreen. It provides an alibi for the drug companies who added mercury to vaccines at levels 250 times higher than hazardous waste levels (based on toxicity characteristics). It provides an alibi for the CDC, FDA, the American Academy of Pediatrics and the other drug company cronies who are responsible for the safety of our children. It provides an alibi for the pediatricians who administered this poison. It provides an alibi for health insurance companies so they don’t have to pay for treatment for these sick kids. It provides an alibi for psychiatrists so they can force powerfull anti-psychotic drugs on these kids who are already terribly confused.

    There will never be an identifiable cause for autism. There are though 18 published papers which identify the underlying medical condition of autism as neuroinflammatory disease. My favorite is ‘ Neuroglial activation and Neuroinflammation in the Brain of Patients with Autism’. This was published by John Hopkins University. Now, do you want to debate whether mercury, a known neurotoxin, added to childhood vaccines at levels 250 times higher than what the EPA identifies as hazardous waste, causes neuroinflammatory disease? Do you want to debate whether brain damaged kids behave in a way so that some psychiatrist can label them as somewhere on the ‘spectrum’?

  8. Mark

    @Joe: Poe’s law

    I think the same mechanism causes many groups to shun people of different beliefs. It seems to allow them to demonize other groups making them easier to dismiss. The more people I see that believe the same as me the more likely I am right.

  9. April Brown

    That actually makes a lot of sense – one of the points I took away from Eric Hoffer’s book True Believer is that real true believers are likely to suffer from multiple “damascus road” style conversions throughout their lives, often believing something fervently, then abruptly believing a new thing.

    The most glaring example of this I ever saw was some Catholic priest who had a website dedicated to proving that acupunture was satan worship. In the midst of the tortured explanations, he revealed that he used to be a devout pagan, and then something glorious happened and he was saved, became a priest, etc. Before being a pagan, he’d been some protestant variety of Christian. Among the things about this man that hurt my brain was that he could have been so adamant about his faith, and then abandon it for an opposing dogma.

    This idea that the uncertain ones are the loud ones does certainly explain a lot. Thanks for posting this.

  10. Toos

    Joe, I don’t understand what you are arguing for. Here in the Netherlands, for years no mercury at all is added to vaccins. Though autism here is as frequent as in the USA. And in most cases not treated with drugs.
    Further I don’t understand what this has to do with what Ed is telling here above. Unless you are trying to prove the message in it?

  11. I don’t think those that replied understand what is being presented by this article. I tried for years to make my wife and children understand and believe my thoughts/beliefs and at times as we all do ‘SHOUT’ my beliefs at them. They all choose to go forward with their own understandings and not my forceful but ineffective diatribes. As time has taken me and my family into our older years, I have lessoned my forceful attitude and beliefs upon them and they have started to create their own. Albeit that they have started to do what I tried to force upon them, but at their time line and not mine. David Gal and Derek Rucker need to entertain a longer timeline. As Toos said; trying to prove ‘What?’

  12. The conclusion is a timely warning; we’re in the midst of a mayorial election campaign here. The next stage of research that would interest me would be to test the converse. If you bolster someone’s confidence, would that person be more receptive to considering evidence that runs counter to that person’s previous beliefs?

  13. Kim

    I wonder if this explains the increasing number of Expanding Earth believers that I’ve encountered?

    I read about S. Warren Carey’s expanding Earth idea (proposed in the 1950-60’s, and quickly rejected in favor of plate tectonics) when I was in college in the late 1980’s, while I was taking an upper level class in plate tectonics. It was the first time I had heard of the theory, and I had never encountered anyone who believed in it. However, I did know older geologists who had never accepted plate tectonics.

    Jump forward 25 years. I’ve seen blog commenters and web sites arguing that plate tectonics is wrong, and that geologists have conspired to hide evidence that the Earth is expanding. I had figured that this was just part of the online world – you can find someone who believes almost anything on the internet. But today, one of my students told me that she had recently talked to a man who wanted to tell her about the Expanding Earth theory, and how there were more and more studies showing that it was true. So in a small town in Colorado, there are now Expanding Earthers trying to convert college students to a theory that was rejected half a century ago, and that had essentially no vocal advocates 25 years ago.

    Are the Expanding Earthers getting louder because the old plate tectonic skeptics are dying off, I wonder, and they are less and less likely to find people who agree with them?

  14. Eleanor

    Been there, do that. When I feel I’m on shaky ground but just before I realise I’m wrong is when I tend to be most voiciferous. Now if I could just recognise this at the time rather than afterwards, then I could be a proper thinking animal rather than a collection of thoughts dominated by impulses!

  15. I was expecting, hoping even, that someone would come along and write a comment along the lines of #7 but Joe completely exceeded all expectations. Kind of proves the point, doesn’t it?

  16. Eleanor

    I was wondering why you’d baited your opening para with vaccines/autism and evolution/ creationism. You missed out AWG though!

  17. tim rowledge

    You missed out AWG though!

    Yeah! Let’s argue about American Wire Gauge! It’s a conspiracy to confuse people!


  18. Toos

    Thanks Ed for your very interesting post as well as for #15. I really thought there could be something wrong with my comprehensive capabilities in foreign languages and/or countries [#10]. Yes, sure for me #7 kind of proves the point by now!

  19. The Other Kim

    Amazing. I think that sometimes people shout out of pure frustration when someone won’t admit to the obvious. Take the old vaccine preservative thimerosal and autism bit. Multiple double blind studies in the late 1990’s demonstrated that there was as essentially zero correlation between autism and thimerosal. In fact, it was removed from almost all vaccines by 2003. Yet I still hear people, like Joe, coming up with all these non-existent correlations or conspiracy theories. Related to the article – why do people not simply look at and accept overwhelming data a face value? Why do people keep beating dead horses? That’s what wants to make me shout. (And if anyone really cares to check, the rather significant rise in diagnosed autism is directly correlated with the increased number of symptoms that are being labeled by medical researchers as autistic. Amazing.)

  20. Zach Miller

    I’d be interested in a psychological study examining why certain groups (like anti-vaxers and creationists) continue to trot out arguments that have long been proven invalid or moot. In those two examples, you can bring up thimerosal in vaccines and the absence of transitional forms in evolution. Both points have been thoroughly destroyed, yet the nuts keep epousing them as if no answers were ever provided.

  21. Phyllograptus

    This makes me think of those cases of strident, hardcore American evangelical preachers denouncing homosexuality to the extent that they can only be called rampant homophobes, who later are caught in homosexual relationships.
    I’m always a little leery of the overlying zealous and usually suspect that their zealotry is covering for their own insecurity regarding the issue they are so zealous about.
    PS long time reader, but have never bothered to comment before, while I’m at it. Congratulations Ed on the award. Very deserved. Always an enjoyable read. Keep it up!

  22. I thought it was a known fact, generally, while arguing most people cling more on to their argument, the greater the opposition. It could also be due to the fact that a belief was well reasoned out in one’s own mind, before cementing it as a belief and the reasons forgotten in due course and just the result kept at easy access memory. Then someone someday comes up with a seeming contradiction to that belief and the time-consuming reasoning does not surface up immediately, just the fact that it was actually considered and ruled out.
    But then there are people that do no reasoning at all for the fear of losing their beliefs of convenience, such as the religious ones.

  23. Shade

    Sorry about this, I usually comment on the article, but these made me re-read the same paragraph because I thought I missed a part.

    “In their second experiment with 151 fresh volunteers, Gal and Rucker found the same effect. This time, they influenced the recruits’ degree of confidence by asking half of them to relate memories where they were brimming with certainty, and the other half to describe —relate memories— where they were plagued with doubt[.] Afterwards,”

    Liked the article, just got stuck on these two grammatical points…
    Sorry to pester with this :-/

  24. Bob

    I find your baiting unprofessional, Mr. Yong. Poor people like Joe are easily swept into their fits because you find pleasure in poking people with sticks.

    I do believe it is noteworthy to consider where these shouters come from, however, and I would personally offer that most readers/listeners are more comfortable with believing a claim by others than looking for the truth themselves. I’m sure everyone here has read of nearly any substance or activity causing cancer, or that the world is flat, or that people a certain color or ability are better/worse than others. (Now that I think about it… Hitler did shout a lot, didn’t he?)

    Creationism is, by the way, a two-sided shouting match. If you don’t believe me, try presenting an honest evaluation of Intelligent Design in a local college (bring earplugs).

    The study itself, however, was delightful. I’m intrigued as to where the study goes from here.

  25. James

    What’s troubling is that every position has a “shouter.” Does it then mean that each position is therefore false? And should we be careful not to judge too harshly those who have doubts as necessarily meaning their beliefs are incorrect? Isn’t a good thing to weigh out one’s thoughts? It seems to me that there are quite a few things we take as truth that if we scratch the surface we find they are based on beliefs that are unprovable. And this later state, doesn’t mean that they are untrue either.

  26. SHFT

    @Joe (#7) Yeah, I’ll debate you, it’s fruitless though, because all you’re doing is proving the point of this article. The wonderful thing about spouting numbers is that they can be checked, and shame on you for not citing your sources, but I’ll let that go, just this once.

    First off, MOST vaccines don’t contain mercury. And haven’t since 2001.

    The ones that do have a significantly small amount (25 ug (micrograms) at the very most)

    Now here’s the real kicker, you say that the toxic reference dose is fixed at 250 x the recommended. But the reference dose is variable to how much you weigh.

    Let’s compare the amount of mercury in a vaccine to a can of tuna.

    consider this little math problem right here http://www.pbs.org/now/science/mercuryinfish.html

    * Multiply child’s body weight by EPA’s reference dose.
    * Convert 45 pounds to kilograms = 20.45 kilograms
    * 20.45 kilograms x .1 micrograms per kilogram per day

    EPA RECOMMENDED LEVEL = 2.05 micrograms per day = 14.35 micrograms per week.


    * Multiply amount of fish by average mercury level for chunk white albacore.
    * Convert 6 ounces to grams = 170 grams 170 grams X .31 ppm (or micrograms per gram)**

    MERCURY INGESTED = 52.7 micrograms per gram


    * Divide 52.7 micrograms by 14.35 micrograms = 3.7


    That means Joe, that a can of tuna has over 2x as much mercury as a flu vaccine

    I will give that you’ve done a little bit of research because of what you said here:
    |Vaccines can’t cause autism. Autism is simply a term from the psychiatric DSM-IV manual.

    However I strongly encourage you to check your sources before someone comes and calls bullshit on you.

  27. Juicyheart

    This study doesn’t really explore people holding onto beliefs, in the face of contradictory evidence. It only says confident/ secure people need less validation from others than unconfident/insecure people. It’s more illuminating in why impoverished people are more religious and fundamental, than it is of why people double down in face of contradictory evidence. I’d be more interested how confidence/inconfidence change a person engagent with evidence contradictory to a deeply held belief, whether there is an effect on if the evidence sways their opinion and what happens to their advocacy.

  28. Jeremy

    Thus the ever louder and more extreme religious evangelicals in the face of titanic evidence against their version of god and the Bible. Not to mention Islamic fundamentalism.

  29. Perry

    Way to handle that Joe dude Ed (and your followers). Who in their right mind still think injecting kids with mercury isn’t safe. There are now more than 20 studies done by the makers, promoters and administraters of vaccines that say there is no link between mercury in vaccines and brain damage. Joe should know better. Way to put him in his place!

  30. It comes as no surprise to me that “Joe” and “Perry” have identical IP addresses…

  31. Joe T

    @”Joe” and “Perry” you needn’t look further than comment 10 (from Toos) for clear, logical refutation of your concern about the link between autism and vaccines. As Ed says, your failure to reconsider your ideas merely reinforce the point of this article.
    The “link” between autism and vaccines can best be described as a conspiracy theory. However, the link between transmission of deadly disease and unvaccinated people is clear and unequivocal — as most recently demonstrated by the spate of whooping cough deaths in California. The worst part is that the babies who are dying are the ones too young to receive the vaccine — but who’ve likely contracted the disease from older children whose parents chose not to vaccinate them. Way to go, conspiracy theorists.

  32. Mel

    This goes a long way toward explaining the deeply entrenched knee-jerk reaction seen by many Law Enforcement officials when presented with the idea of legalizing/decriminalizing marijuana. Medical Marijuana’s success has certainly shaken their core belief of cannabis being the demon weed, especially as they witness friends and family members enjoying an improved quality of life when medicating with cannabis. I had always seen this as a financial issue – that Law Enforcement wants to keep both hands on the cannabis cash cow, but seeing that there might be underlying issues such as described here is enlightening, Thank you for the insight.

  33. Carl

    Very interesting – thank you. These studies reinforce the Covey 7 Habits Approach. You should read the original book. It’s all about relationships. If you support someone, give them respect, they tend to trust you more. It happens in a one minute exchange. If you want to persuade them, first listen to them and reflect what they say and feel. Especially reflect their feelings back to them, so they know they are heard. It builds their confidence and self esteem, and also their regard for you and your opinion.

    When you have that built up – and it can happen in just a few minutes – then you explain your persepctive. They are much more open because they are no longer threatened. It is a stellar negotiating technique.

    Thanks for pointing to the research.

  34. Steve

    How does this apply to the Tea Party Folks

  35. Ted N.

    This very much explains the Tea Party folks. IMHO, they cannot express their real fears, so they make stuff up and yell about it. They are also easily manipulated by Tea Party leaders, so they may have doubts that the Tea Party message aligns with their own views.

  36. Fulana

    Brilliant Headline–catchy, yet actually accurate.

  37. Matt

    @ #9. April Brown. DE candidate for Senator Christine O’Donnell is another good example of someone flying from one extreme to another, never stopping in the middle.

  38. Greg L

    Beware of studies that overstate the impact and applicability of their findings. Yes, psychologists and many others have known that many people become defensive and unwilling to listen when they are directly challenged, especially regarding strongly held core beliefs. That is not news. And insecure people often become more vociferous and defensive. Again, not news.

    It does not mean, however, that it applies to all people in all situations. These studies are based on immediate responses, they do not reflect what may happen over time to the listener, and the groups tested seemed rather limited in terms of a broad cross-section of the population. It does not take innumerable factors into account. It is a mistake to view these limited experiments as a general rule that vitiates the need for a multitude of approaches that are needed to win over a wide spectrum of people to the movement.

    Please, let’s stop trying to prove that there is only one way to sway people’s opinions. We don’t know what will be most effective with all people. Everyone responds differently based on innumerable factors. But, if we continue to focus on internal issues like this that will never be resolved, we are focusing our efforts in the wrong direction. Give people more credit to take the time to reflect even if they are initially turned off by strong advocacy. One size does not fit all.

  39. @Pam D – Those who consider themselves consummate doubters simply aren’t. They are believers in consummate doubt. True doubters are not sure they’re doubters :)

  40. Richard

    Just because someone is a “shouter” doesn’t mean they are a doubter. Granted, if they are a doubter they are more likely to be a shouter, but people can be shouters for many reasons. They could believe passionately and wholly and be genuinely trying to persuade you. They could be natural shouters. They could be right.

    It always annoyed me when people who were “gay bashing” were described by detractor as “definitely gay”. That might be the case, but they might simply hate people who were gay. Instead it was usually a way of avoiding actually engaging with them, pouring scorn and laughing. Which weren’t taking engagement with the person, or the actual issue forwards. A loss for everyone. (see Carl and Wayne for better ways).

    What’s interesting is how many people here have used exactly that technique to attack the people they dislike rather than honestly question themselves and their motivations. If there’s one thing that articles like this, those on cognitive dissonance and bias towards belief over rationality show, it’s that we should be profoundly careful when we cast the first stone.

    I’m aware of how I reacted when I was confronted by a load of anti-global warming stuff a year ago. I’d looked at it when I was younger, and generally disliked the people who opposed it, so I’d felt confident of my position. When I was forced to question it properly I found it really difficult. My first reaction was to resort to abuse, ignore it, or start to seek stuff that would confirm my views. A fair bit of reading Wikipedia later, and a good rummage around the Sceptical Science website, I felt much better informed and more confident in my beliefs.

    But then again all I’ve done is sought out sources which agree with me. Yes I did have a rummage around on websites that held the opposite opinion, but not with the same enthusiasm.

    Global warming isn’t something that defines me or my life. It may affect my lifestyle choices, but I’d still be me if I changed my mind. But I really didn’t want to. And if it applies to something like global warming how much more when it applies to something that matters profoundly to me- my political, moral or religious beliefs. Quite how much can I trust myself to be rational?

    This is a very interesting article, but needs to be taken with a lot of other information on how we believe and choose, and with a strong ability to doubt ourselves.

  41. Richard

    Hmmm, that last line comes across as a bit sanctimonious. Apologies.

  42. SHFT, Your comparison of mercury in a can of tuna to mercury in a vaccine is interesting, but you omitted the major difference. Vaccines are injected past the immune system into an infant whose existing immune system and neurological systems are highly vulnerable, undeveloped.

    No one needs “science” to know the problem with vaccines. Just observe an unvaccinated child. Health shines forth. A major difference.

  43. Toos

    Jim West, would you say the same, seeing that unvaccinated child 1 1/2 years old, dying from whooping-caugh [as has happened in my family when prevention wasn’t possible yet]? Do you know what tetany can do to someone unvaccinated? And so on. A major difference indeed …

  44. Shade

    I found this article interesting, but I dare say the comments more so.
    On the one hand we have several people adressing the articles real point, but as soon as one person took the bait a chain has built following this one person. Even though it has been said that it was bait people are still following it…

    Thanks for the article, but as people have said, many more factors to consider. Unlike what others have said this is one of them, and this is how every previous factor has been presented; as the one significant factor.
    Not much different from most studies I have read, so just add it to your tool box 😉

  45. John

    This kind of information on psychology is especially interesting when applied to the circumcision “debate”. The sheer intensity those arguments can climb to is fascinating.

    Personally I’m against doing it, and I state this as one who had it forced upon him as a wee babe with no say in the matter. Why go about attempting to fix something that isn’t broken? It just makes better sense not to. (to me)

    Now for the fun part; I wait and see if a storm of controversy will start simply because I brought the subject up and tossed my own viewpoint out there.

  46. John

    This so applies to believers in copyright and other IP and legal magic fairy dust which always tends towards the maximum despite evidence or even consideration of pragmatical limitations. The concept that ideas can be someone’s property is so unreasonable yet also so very sticky to the human mind.


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

Not Exactly Rocket Science

Dive into the awe-inspiring, beautiful and quirky world of science news with award-winning writer Ed Yong. No previous experience required.

See More

Collapse bottom bar