We all jump to conclusions from time to time, but some people have a persistent problem in this regard, spending little time pondering before making decisions. For example, about 20 per cent of people spend more time planning their holidays than planning their financial futures. In psychology, making decisions based on very little evidence is called a cognitive bias and is often part of a larger defective pattern in behaviour and thinking. This phenomenon is clearly explained by Carmen Sanchez and David Dunning, who research human misbeliefs, overconfidence and decision-making, in Scientific American, (October 2021).
Before going further here is a little test described by Sanchez and Dunning that may indicate whether or not you tend to jump to conclusions. A bat and a ball together cost €1.10. The bat costs €1 more than the ball. How much does the ball cost? The correct answer to this problem is at the end of this article.
Sanchez and Dunning studied a sample of 600 people in the general population, using a thinking game commonly used in researching schizophrenia, a condition in which jumping to conclusions is common. Players in the game observe someone who is fishing one of two lakes. In one lake most of the fish are red, in the other grey. The fisher catches one fish at a time and stops when the player decides he/she knows which lake is being fished. Some players decide only after seeing many fish landed, others (conclusion-jumpers) decide after one or two fish are caught.
Sanchez and Dunning tell us there are two pathways of thought — automatic and controlled
The researchers found that the fewer fish players needed to decide, the more errors and the more mistakes they make in other types of belief, reasoning and decisions. For example, they are more likely to believe in conspiracy theories such as that the Apollo moon landing project was faked or that there is a Government/medical conspiracy to hide the link between radiation from mobile phones and cancer. And when gambling they are more likely to choose riskier bets with less chance of winning. They also displayed an abnormally high level of confidence. The difference between the impetuous and the cautious decision-makers remained even when intelligence and personality differences were taken into account.
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Sanchez and Dunning tell us there are two pathways of thought — automatic and controlled. Automatic thinking pops up ideas easily and spontaneously. Controlled thinking requires conscious reasoning and effort. The researchers found that those who jump to conclusions and those who think things through are equally confronted by automatic thinking but those who jump to conclusions do not engage in controlled reasoning to the same degree as those not so prone to jump to conclusions. Controlled thinking helps to counterbalance the biases introduced by automatic banking.
Sanchez and Dunning believe that automatic thinkers can be helped by special training adapted from schizophrenia research to target their biases and help them to think more deliberately. They adapted a method from schizophrenia research called metacognitive training that aims to get people to see their own thinking patterns and to intentionally adjust them in line with evidence. For example, it exposes trainees to examples of problematic thinking like overconfidence, jumping to conclusions, and single-cause explanations. Trainees also practice externalising their thinking in writing or speech, reflecting on it, and pushing back against it using more rational and analytical thinking.
Thinking things through rather than jumping to conclusions is important to all of us and studies have shown that gathering even a small bit more evidence helps to avoid major mistakes
The training proved at least partially successful with the population studied by Sanchez and Dunning. In particular, it reduced the overconfidence usually associated with jumping to conclusions.
Up to two-thirds of people with schizophrenia delusions also jump to conclusions when solving simple abstract probability problems, compared to about 20 per cent of the general population. Sanchez and Dunning hope their work with the general population will fill in some gaps in knowledge that will help people with schizophrenia.
Thinking things through rather than jumping to conclusions is important to all of us and studies have shown that gathering even a small bit more evidence helps to avoid major mistakes. This work by Sanchez and Dunning is a very valuable and practical application of social psychology.
Answer to test: The ball costs 5 cent. Automatic thinkers may jump to the conclusion that the ball costs 10 cent but a little patience in thinking the matter through gives the correct answer.
- William Reville is an emeritus professor of biochemistry at UCC