Substitution answers an easier, similar question instead
When faced with a difficult question, we often answer an easier one instead, usually without noticing that we have done so.
The question that the executive faced (should I invest in Ford stock?) was difficult, but the answer to an easier and related question (do I like Ford cars?) came readily to his mind and determined his choice. This is the essence of intuitive heuristics: when faced with a difficult question, we often answer an easier one instead, usually without noticing the substitution.
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If a satisfactory answer to a hard question is not found quickly, System 1 will find a related question that is easier and will answer it. I call the operation of answering one question in place of another substitution... People are asked for a prediction but they substitute an evaluation of the evidence, without noticing that the question they answer is not the one they were asked. This process is guaranteed to generate predictions that are systematically biased; they completely ignore Resources/Garden/Regression to the mean.
source: Thinking, Fast and Slow – Kahneman (2013) § “Taming Intuitive Predictions”
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