What is Illusion of Validity?

Illusion of Validity is a mental model used for better thinking and decision-making.

How do you apply Illusion of Validity?

To apply Illusion of Validity, identify situations where this framework is relevant, then use it as a lens to evaluate your options and decisions. The model is most useful when combined with other complementary mental models.

What category does Illusion of Validity fall under?

Illusion of Validity falls under the Psychology & Behavior category of mental models. Other models in this category can be found on the Psychology & Behavior hub page.

Why is Illusion of Validity important?

Illusion of Validity is important because it provides a structured way to think about problems that would otherwise be approached with intuition alone. Understanding this model helps you avoid common reasoning errors and make better decisions.

Where does Illusion of Validity come from?

Illusion of Validity is discussed in the tradition of Kahneman / Tversky.

Psychology & Behavior

Illusion of Validity

Model #0933Category: Psychology & BehaviorSource: Kahneman / TverskyDepth to apply:

4 min read

Contents

1. Core Idea
2. How to See It
3. How to Use It
4. Founders & Leaders
5. Connected Models
6. One Key Quote
7. Summary & Further Reading

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Psychology & Behavior

Section 1

Core Idea

The Illusion of Validity is the cognitive bias where high confidence in a judgment persists even when the evidence underlying that judgment is known to be unreliable. When information forms a coherent story, people feel confident in their prediction — regardless of whether the information actually has predictive power. A compelling interview performance creates strong confidence in a hire, even though unstructured interviews are poor predictors of job performance. A neat narrative about why a market will grow creates strong conviction, even though the data is ambiguous. The illusion is driven by coherence: when the pieces fit together into a satisfying story, the brain registers confidence — even though internal consistency says nothing about external validity.