What are zombie ideas? These are ideas that keep coming back, even though they have been thoroughly refuted by the evidence. They should be dead, but they won’t stay dead! They keep coming back because they serve certain interests or prejudices (or both). Here are six zombie ideas in crowd psychology that keep cropping up in everyday talk, in the news, among policymakers and practitioners, and in academic publications. And here’s why they’re wrong.

1. De-individuation

The most distinctive claim in the ‘de-individuation’ family of theories was inherited from Gustave Le Bon – the idea that being anonymous leads to a loss of self and hence uncontrolled, anti-normative behaviour. This idea could not cope with the evidence that conditions of anonymity in fact are associated with a wide range of behaviours, including accentuation of pro-social behaviours. There is little evidence that anonymity leads to a ‘de-individuated’ state of reduced private self-awareness. Rather, anonymity makes group identities more salient and hence leads to more, not less, conformity to relevant situational norms.

Key reading: Postmes & Spears (1998)

2. Groupthink

While groupthink is supposedly a pitfall of small groups and organizations rather than crowds, I include it here as it’s another example of an anti-collectivist concept. It is used loosely by commentators to refer to any situation where group members prioritise the group’s own ideas over critical or external views. For example, some of those involved in decision-making at the height of the Covid pandemic have used the idea of groupthink to explain organizational failures in decision-making. The distinctive claim of the ‘groupthink’ concept is that highly cohesive groups will be subject to concurrence-seeking at the expense of critical inquiry, leading to faulty decisions. A big problem for this idea is that there is not much evidence that greater cohesiveness leads to worse decision-making. Rather than the tendency to ignore critical evidence being a function of groupness, it’s more likely to be an effect of particular group norms (for example that value loyalty).

Key reading: Aldag (2022)

3. Mass panic

Aside from the profound problems of judging whether behaviour counts as ‘panic’ in an emergency (what is reasonable behaviour in this situation?) and the related problem of trying to import a polysemic everyday term into scientific explanation, there is another basic problem. There is no evidence that people in crowds are typically uncontrolled, selfish or competitive behaviour in emergencies. The common finding of social support among people in emergencies adds to the problems of this concept.

Key reading: Clarke (2002)

4. Contagion

One of the most popular concepts in the social and behavioural sciences, ‘contagion’ is often used synonymously with spread and social influence. But there is little evidence that mere exposure alone is sufficient to prompt emulation. Group boundaries in the transmission of behaviours and emotions demonstrate this. Even for supposedly basic processes like so-called emotional contagion, reviews of the evidence suggest that the mimicry involved is not automatic, but rather relates to communication goals that already involve an emotional orientation to the other person.

Key reading: Drury et al. (2019)

5. The hooligan

The hooligan is a concept from sociology more than psychology, but it is a good example of a dispositional explanation. For the earliest beginnings of crowd psychology as a science, some have claimed that crowd conflict occurs through the convergence of certain kinds of individuals (usually with criminal, violent, or poorly socialized dispositions). From the 1960s urban riots in the USA to the 2011 English riots, proponents of such ideas have failed to produce the required evidence. In the football context, of course some groups seek conflict, but this in itself can’t explain collective behaviour. As Stott and Pearson explain, the concept has little explanatory power: ‘disorder’ sometimes occurs when known ‘hooligans’ are not present; and when known ‘hooligans’ are present, ‘disorder’ doesn’t always take place.

Key reading: Pearson & Stott (2022)

6. Mob mentality

An overarching zombie idea, that links many of the above, but which also includes the distinctive claims that in crowds people revert to a simpler, less intelligent, and more primitive or archaic psychology, under the influence of which behaviour tends to barbarism, loss of control, and violence. The fundamental problem here is two-fold. First, if this is a real tendency it cannot easily explain the majority of crowds, which are peaceful and pro-social. Second, the suggestion of a universal tendency like this cannot explain the form of behaviour when there is crowd violence. To explain the distinct targets of the sans culottes, urban rioters, and football fans, and the sophistication in even the most violent crowd it makes better sense to refer to their identities, group norms, and values.

Key reading: Reicher (1984)