Cognitive biases

A long read

Your brain takes shortcuts

Your brain has too much to handle.

So it takes shortcuts to think fast. The shortcuts help most of the time.

Your guess

A bat and a ball cost $1.10 together. The bat costs $1.00 more than the ball. How much is the ball?

The shortcut fired in the wrong spot. Brains make this same mistake again and again.

Tversky & Kahneman (1974). Judgment under Uncertainty: Heuristics and Biases. Science 185:1124–1131.
Kahneman, D. (2011). Thinking, Fast and Slow. Farrar, Straus and Giroux.
The Decision Lab — Biases & Heuristics index (https://thedecisionlab.com/biases)

SimplyPsychology — Cognitive Bias overview (https://www.simplypsychology.org/cognitive-bias.html)

Read end to end and corrected: August 8, 2026. Numbers checked: August 8, 2026.