Psychologists often describe thinking as operating in two modes. System 1 is fast, intuitive, and automatic, while System 2 is slower, more deliberate, and analytical. Although intuition is efficient, it can lead to predictable errors when problems require logic, probability, or careful attention to assumptions.
This 20-question System 2 Thinking Test draws on decades of research into cognitive reflection and reasoning. It's not an IQ test, but a way to assess how often you engage effortful thinking when faced with deceptively simple problems.
Frequently Asked Questions
How long does this quiz take?
It takes about 10 to 15 minutes to complete, depending on how carefully you work through each question.
Is this an IQ test?
No. This test measures cognitive reflection and logical reasoning, which are related to but not the same as overall intelligence.
Why do some questions feel misleading?
Many questions are designed to trigger intuitive responses that may be incorrect unless you slow down and analyze them carefully.