"Humans are herd animals" — the line is offered quickly, usually as a put-down. But is it true, and how good is the evidence? The short answer: that humans orient themselves remarkably strongly toward the group is one of the best-established findings in social psychology. The word "instinct", however, is misleading — what the research shows is not a blind drive but an explainable mechanism, one that can also be broken.
Asch's Line Experiment: Conformity Against One's Own Perception
The best-known evidence comes from Solomon Asch (1951). Participants had to judge which of three comparison lines matched a reference line in length — a trivial, unambiguous task. But when several confederates in the room unanimously gave the same obviously wrong answer, participants went along with the group error in about 37% of the critical trials. Across all participants, roughly three in four conformed at least once, against what they saw with their own eyes. The experiment has been replicated many times.
Sherif: How Norms Arise in the First Place
Earlier, Muzafer Sherif (1935) had studied the reverse case — not an unambiguous task as with Asch, but a deliberately ambiguous one. He used an optical illusion, the autokinetic effect: if you stare at a single stationary point of light in a completely darkened room, after a short while it appears to drift around. In reality it does not move at all — in the dark the eye simply lacks the reference points it could anchor to, and so it "invents" a movement. That is what makes the experiment so clever: there is no correct answer to orient oneself by.
Sherif asked participants to estimate how far the point moved. First each person sat alone in the room. As expected, the estimates varied widely — one said 2 centimetres, another 20. Each formed their own very personal yardstick.
Then Sherif brought several people together, who now spoke their estimates aloud. Without anyone prompting them, the figures moved of their own accord toward one another, until the group had "settled" on a common range — a self-generated group norm. No one decreed it, no one voted on it; it simply emerged through interaction.
The truly striking part came at the end: when Sherif later put the people back in the room one at a time, they held on to the shared norm — no longer to their original, personal estimate. The group was long gone, yet its yardstick remained and had become their own from within. This is exactly what distinguishes Sherif from Asch: with Asch people conformed outwardly, against their better judgement. With Sherif there was no better judgement — and so they genuinely adopted the group's view, lastingly. It is the model for how social norms, tastes and "things taken for granted" arise: first negotiated together, then felt as one's own conviction.
Social Proof in Everyday Life
Robert Cialdini calls the principle "social proof": under uncertainty we take other people's behaviour as a cue to what is correct. Stanley Milgram's street experiment shows it vividly — if a few people stop and look up, the whole crowd soon does too. The same principle underlies "bestseller" labels, star ratings and canned laughter in comedy shows.
Markets and Crowds
Beyond the lab, herd behaviour is well documented too. In behavioural economics it helps explain bubbles, crashes and bank runs (e.g. Robert Shiller); such dynamics can be formally modelled as information cascades — each person infers from the behaviour of those before them and so amplifies a movement no one would have chosen alone.
What Happens in the Brain
Neuroscience has made the effect visible. In a much-cited fMRI study (Klucharev et al., 2009), deviating from the group opinion produced a kind of neural "error signal", and conforming to the group subsequently changed even the reward valuation — people afterwards genuinely liked what the group liked. Conformity, then, is not merely going along on the surface; it reaches into how we evaluate things.
Why "Instinct" Is the Wrong Word
As robust as the findings are — the term herd instinct suggests an innate, inescapable drive as in a flock of sheep. That is misleading. The research instead describes two explainable mechanisms:
- Informational influence — others may know more than I do; orienting toward them is often simply rational.
- Normative influence — I want to belong and not stand out.
And the effect is highly context-dependent: where the facts are clear, conformity drops sharply. In Asch's setup a single dissenting ally is enough to break the group pressure dramatically (by up to about three quarters). And depending on culture, conformity varies. People can therefore resist the pull — especially with allies and with clear facts.
Culture: Where Conformity Runs Higher
That "culture" makes a measurable difference here is not just an impression. A large meta-analysis by Bond & Smith (1996) pooled 133 Asch replications across 17 countries and found two clear patterns:
- Collectivist vs. individualist. In more collectivist cultures — where the group, harmony and "face" rank high (often cited: parts of East and Southeast Asia, many African and Arab societies) — conformity was on average higher than in individualist cultures (USA, Western Europe), where independence is part of the self-image. There, fitting in is less a "weakness" and more a social virtue.
- Zeitgeist. Within the USA, Asch conformity declined over the decades — a hint that the strength of the effect also depends on the social climate, not on some fixed "human nature".
A concrete picture: someone who grows up in a class or company where dissent counts as a disturbance of harmony pays a higher social price for a deviating opinion — and is more likely to keep quiet. Where dissent counts as a normal part of negotiating, speaking up comes more easily. The reading matters, though: these are averages, not character verdicts about whole peoples, and within every culture context still decides — among strangers people often behave differently than within their own group.
And School?
The obvious question: does school, of all places, train us to go along? Careful — there is no clean experimental "school system → Asch score" study; what follows is a reasoned application of the two mechanisms, not a measured finding. But the direction is plausible. What matters is whether a system raises the normative pressure (belong, don't stand out) or defuses it.
What tends to foster herd behaviour — and these are precisely features of the Prussian school model that still shapes the form of our schools today:
- One right answer, defined up front. When knowledge appears as "testable / right or wrong", you learn to orient toward the expected answer — informational influence in its purest form.
- Grades and ranking. Being graded and compared makes you pay close attention to what the teacher and the group expect. Deviating costs — so you conform.
- Lockstep by year group. Class cohort, 45-minute periods, everyone doing the same thing at the same time: this models "everyone does it this way" as the default.
- Rewarded compliance. Where sitting still and going along count for more than questioning, dissent becomes a risk rather than a virtue.
What works against it — features that make deviating safe and examining normal:
- A culture of error and debate. Where mistakes are part of learning and reasoned dissent is explicitly welcome (discussion, the Socratic method, "devil's advocate"), normative pressure drops — the "dissenting ally" becomes the rule, not the exception.
- Individual pace instead of lockstep. Montessori, Rudolf Steiner's Waldorf pedagogy (no numerical grades in the early years, no holding back, learning at one's own rhythm), project- and inquiry-based teaching, or the (long less centrally examined) Finnish model rely more on independent work than on reproducing a model answer in unison. The honest flip side: a reform school with a strong worldview can become its own norm bubble too — what matters is still whether reasoned dissent is welcome.
- Understanding instead of reproducing. This is exactly where the critique of Vera F. Birkenbihl and the methods of Ricardo Leppe come in: someone who has genuinely grasped a subject needs the group less as an anchor — they have "clear facts", which Asch found to be the strongest antidote.
The fair assessment: no school can (or should) abolish norms — a degree of orienting toward others is often simply rational. The difference lies in whether a system punishes or protects reasoned dissent. And this holds symmetrically: an "alternative" or especially convinced group can become an echo chamber too. The antidote stays the same as throughout this piece — examine first, then judge.
Why This Is Here
For the themes of this site this is more than a footnote. Herd behaviour explains a good part of why uncomfortable or unfamiliar findings — say on near-death experiences (e.g. the Pam Reynolds case, van Lommel's Lancet study or Jeffrey Long's case database) or mediumship (e.g. Gary Schwartz's VERITAS experiments, Julie Beischel's Windbridge studies or William James on Leonora Piper) — are reflexively dismissed without examination. The same dynamic is traced through historical cases (Galileo, Semmelweis, Wegener) in Majority versus Experts, and the psychological defence patterns themselves are covered in The Psychology of Skeptical Defence. The symmetry matters, though: conformity works in every direction — a group of believers can just as well follow a norm rather than the evidence. Which is exactly why the same stance helps here as everywhere: examine first, then judge — and a measurable social effect is not yet a verdict on the content of a belief.
Sources
- Asch, S. E. (1951/1956): Studies of independence and conformity: A minority of one against a unanimous majority. Psychological Monographs 70(9) — line experiment, ~37% conforming judgements, effect of a dissenting ally.
- Sherif, M. (1935): A study of some social factors in perception. Archives of Psychology — autokinetic effect, norm formation.
- Bond, R. & Smith, P. B. (1996): Culture and conformity: A meta-analysis of studies using Asch's line judgment task. Psychological Bulletin 119(1), 111–137 — higher conformity in collectivist cultures, decline over time.
- Cialdini, R. B. (1984): Influence: The Psychology of Persuasion. — "social proof".
- Klucharev, V. et al. (2009): Reinforcement learning signal predicts social conformity. Neuron 61(1), 140–151.
- Shiller, R. J. (2000): Irrational Exuberance. — herd behaviour in financial markets.