An introduction to catastrophe theory

Date: 07/07/2021 Written by: Daisy 3 minutes to read.
Understanding group behaviour

In this latest blog, our Social Researcher and Data Analyst Daisy introduces us to Catastrophe Theory and how it can explain sudden changes in human behaviour and why it might be relevant in today’s political and cultural landscape…

I was introduced to Systems and Catastrophe theory during my time at university, and despite it being relatively unknown, I found it to be a fascinating way to understand and account for group and crowd behaviour.

What is Systems theory?

Systems theory proposes that people should be studied as a collective rather than individuals in order to account for the impact that we have on one another. People act as components of a complex system, in which each component influences, relates to and depends on one another. Small changes to systems can lead to sudden, drastic changes in its behaviour, which can in some cases seem as if they’ve come out of nowhere.

Catastrophe theory – a branch of systems theory – attempts to account for these sudden, seemingly drastic changes (Flay, 1978), with one model specifically accounting for how different levels of control variables can lead to a sudden, rather than gradual change in a system. It compares this shift in behaviour to that of particles; when a temperature threshold is reached, they shift between a solid, liquid and gas, and the intensity of the temperature controls how quickly this change happens. If we were to apply this to human behaviour, just think of the particles as people.

How do particles apply to human behaviour?

Systems and Catastrophe theory can be used to account for crowd behaviour, where the crowd acts as the system and people its components. Merely being a part of a group or crowd is enough to change people’s behaviour and so studying individual behaviour would be futile; in some cases, people can even lose their sense of self-awareness and engage in extreme behaviours which are completely uncharacteristic of themselves. Zimbardo (1969) refers to this as ‘deindividuation’. This demonstrates how components are influenced by each other and their wider system.

One case study would be the 2011 London riots, where the control variables were the levels of discontent amongst the population and police brutality. There were already high levels of discontent towards brutal treatment by the police, which was coupled with increasing anger towards rising inequalities. However, a shooting acted as a catalyst for rioting to occur; the threshold of behaviour change had suddenly been met and rather than seeing a gradual change through the increase in frequency and intensity of action, we saw behaviour ‘flip’ suddenly from not rioting to rioting. Here we come back to how components of systems are influenced by one another and the system as a whole, and the impact of being part of a crowd on human behaviour, helping to explain how there were people who had never shown any signs of violence in their lives suddenly rioting and looting.

Why is this relevant?

Over the past 12 months, the pandemic has exacerbated inequalities and highlighted social issues more than ever; staying at home has given the nation time to reflect on life as we know (or knew) it and to pay more attention to the social issues prevalent our society. When we think about many of these social issues now, we’ve found that we’ve had enough – people want change. Tensions are high, and more and more people are making their voices heard and are taking action. So far, this increased action has been working to gradually change the political and societal landscape, but with the cusp catastrophe model in mind, this could ‘flip’ at any moment.

A cultural change is imminent – you can sense it in the air – the question is no longer ‘if’ this will occur but instead ‘when’ and ‘how’.

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