Thinking clearly · Chapter 10

How can you avoid confirmation bias?

By Zafar Alam · Building Critical Thinking Habits

Seek evidence that would make your preferred explanation wrong. Decide what would change your mind before collecting more support. You cannot remove bias by promising to be fair; you need a check you can perform.

Ask the opposite question

In two experiments, Lord, Lepper and Preston found that considering the opposite had more corrective effect than instructions to be fair and unbiased. The study concerns particular student judgments, not a cure for all real-world bias.1

I turn that into a habit: if my explanation were wrong, what else could produce this observation? Chapter 10 concerns practices repeated until they become usable when the decision matters.

A second source is not always a second perspective

Two reports may repeat one original claim. Trace them to their evidence, then seek a different test or explanation. More repetition is not more independent support.

A counterargument must be capable of changing the decision. If every result supports the same belief, the belief is not being tested.

A check you can use

  1. Write your explanation and a plausible alternative.
  2. Name a result that counts against your explanation.
  3. Seek it and apply the same standard of proof to both alternatives.

How do you avoid confirmation bias in research?

Set inclusion rules before reading results, keep contrary findings visible and distinguish original evidence from repetition. These are my working checks. The experiment supports considering alternatives, not this entire protocol.1

Zafar Alam

Zafar Alam is a civil engineer and Chartered Construction Manager with about 12 years on major projects. He is the author of What Are We Missing? How to Think More Clearly Before You Decide, planned for 13 February 2027.

Keep thinking

Why did Theranos fail?Chapter 3 · The Bugs in the MachineryWhy did Deepwater Horizon explode?Chapter 1 · The Foundations of Critical ThinkingHow can you avoid the sunk cost fallacy?Chapter 3 · The Bugs in the Machinery

Use this on a real decision

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