Personality & Individual Differences · Simplified
How Much Room Does the Situation Leave?
Whether people look different from one another depends on where you happen to be watching them.
The theatre
Four people, two situations
The same four fictional people are observed in two settings. Nothing about them changes. The only thing you control is how much each setting dictates what anyone does.
Key terms
- Strong situation
- One that tells everyone clearly what to do, leaving little room for people to differ.
- Weak situation
- One that leaves the response open, so what people bring to it shows.
- Affordance
- What a situation gives people the chance to express. Two weak situations can afford different things.
One line per person, joining what they do in the first situation to what they do in the second. Lines that cross mean the two situations put those two people in a different order.
What this shows
Both matter, and they depend on each other
Key idea: Making the setting stronger squeezes people together. That is a fact about the setting, not about the people: the four of them are exactly as different from one another at the end as they were at the start, and it would show again the moment you moved them somewhere that left room. So an observation of very little variation between people is not evidence that people vary little. The second thing on the chart is more interesting than the first. Even when both settings leave plenty of room, they do not put the same person at the top, because they give different things a chance to show. That is why neither "personality matters more" nor "situations matter more" is a defensible summary: what a person brings and what a setting affords determine the behaviour together.
Four invented people and two invented settings, with behaviour generated from a formula rather than observed. Real situations are not arranged along one dimension of strength, people select the situations they are in rather than being assigned to them, and the same setting is not equally strong for everybody. The numbers on the chart are units of nothing in particular. What the model is for is the relationship between constraint, affordance and observed variation, which does hold; nothing here measures any real person or predicts anyone's behaviour.
The longer version adds a ranking prediction before the reveal, more settings, an explicit aggregation demonstration and a transfer exercise. It is at Person-Situation Interaction Theatre in the main collection.