I'm going to answer that age old question, 'would you jump off a bridge if everyone else was doing it?'. You know, since I started this site I've gotten people emailing me about this (and a bunch of other clichéd questions). Only recently has it occurred to me that at the base of an old platitude, often lies truth. And often that truth can be found in the mind.
Social proof (or social influence) is something you've almost certainly heard of before, but rarely is it discussed with any sort of academic rigour. It's the idea that the more other people appear to prefer something, the more likely we are to prefer it ourselves. When other people are interested in something, we tend to get interested ourselves.
People often use the example of 'the study conducted in Russia' to make their point. In the study, a researcher(s) lines up outside a random door on the streets of Moscow. As the researcher(s) wait, random passers-by begin to line up behind the researcher(s). There's no rhyme or reason to it, but people just line up expecting that, since everyone else is lining up there must be something good at the other end.
It's a shame this study doesn't seem to exist.
That isn't to say social proof isn't a thing though. Social proof is evident in the effectiveness of online reviews - think of Amazon, Yelp, Goodreads. It's why 'trending stories' on Twitter and Facebook trend - whether we're interested in them or not, we might be influenced to click on them by virtue of the fact that a bunch of other people seem to dig it. It's why laugh tracks on sitcoms are a thing (and why you tend to find things funnier when people around you are laughing).
There are plenty of studies that show it in action that aren't made up (or heavily elaborated). Like this one, where people are asked to watch a light that looks like it's moving (but isn't). They individually decide how much it's moving and the amount they choose differs from person to person. Then the experimenters bring the people all in together and run the experiment again. This time, the amounts the people decide the light is moving are very similar. One last time, the experimenters show the folk the light, and just like the first time they do it individually. But this go around, instead of coming out with different amounts from person to person, they stick to the group consensus from the last run.
So, why might we do this? Well, the easiest explanation is that it's a kind of evolved response to ambigious situations. Our social nature is extremely important to us (being social is related to living longer - even today). Early on, we realised that by sharing experiences, survival was more assured. So we evolved a tendency to just do what everyone else is doing when it isn't clear how we should act. Unfortunately this little quirk can have some terrifying implications. In that linked article, you see that even when the situation isn't ambiguous, we're more likely to conform. An explanation for that lies in the potential for pain in social rejection and the potential for gain in social inclusion. In fact, social acceptance is so important to us that it's wired in our brains!
So, back to the question. Would you jump off the bridge if everyone else was doing it? Well, you'd certainly be more inclined to. On a very morbid note, when a suicide is widely publicised you often see suicide rates spike briefly in that locality. It's such a common thing it has it's own name - the Werther effect. The reality is, social proof is an influence that's hardwired into us; an effect that will often have a hand in the decisions you make whether you realise it or not. Me personally? I wouldn't bother asking any teenagers this question again. It's time to retire the saying.
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