Conjunction Fallacy
We assume that specific conditions are more probable than general ones.
The conjunction fallacy (also known as the Linda problem) is a formal fallacy that occurs when it is assumed that specific conditions are more probable than a single general one. The most often-cited example of this fallacy originated with Amos Tversky and Daniel Kahneman: 'Linda is 31 years old, single, outspoken, and very bright. She majored in philosophy. As a student, she was deeply concerned with issues of discrimination and social justice, and also participated in anti-nuclear demonstrations.'
What it looks like in the wild.
- Everyday life Linda Problem Given Linda's description, more people say 'Linda is a bank teller and feminist' is more probable than 'Linda is a bank teller' — the conjunction cannot be more probable than either component.
Recognising a definition is not the same skill as spotting it.
Two scenarios from the app, with distractors drawn from the same family of biases — which is what makes them hard.
At the grocery store, Anna chooses the organic, locally sourced brand of pasta, even though a standard brand has better reviews and is more affordable.
Grace thinks it's more probable that her friend, who runs every morning, is training for a specific marathon and also coaches a local running club than that she is just training for a marathon.
Biases rarely arrive alone.
Understand more. Assume less.
188 biases, 18,869 scenarios, and a record of how you actually decide.
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