Five common thinking errors
Confirmation bias
We prefer information that supports an existing view.
Anchoring
The first number or statement influences later judgement too strongly.
Availability heuristic
Easy-to-remember examples feel more frequent or important than they are.
Sunk cost
Time or money already invested keeps us attached to a poor option.
Dunning–Kruger effect
Limited knowledge can make self-assessment unreliable or overly confident.
Thinking errors in learning
- “I read it, so I know it.” → test with active retrieval
- “One problem worked, so the topic is secure.” → change the problem type
- “I am bad at maths.” → name the specific sub-skill
- “The AI sounds certain, so it is correct.” → request sources and an independent check
- “I have already spent so much time.” → reassess the best option from today
The countermeasure is usually concrete: What exactly is the claim, what evidence would disprove it and which alternative has not been tested?
A 60-second thinking pause
- Which decision am I making?
- Which assumption am I treating as certain?
- Which information is missing?
- What would someone with another view say?
- What is the smallest reversible test?
Good thinking does not mean never being wrong. It means discovering and correcting errors faster.