Decisions

Rationality: 6 key ideas

by Steven Pinker

The core ideas of Rationality, each in under a minute, written in our own words. Want the full depth? Get the book.

1. IDEA 1 OF 6

   Rationality is a toolkit

   Logic, probability, statistics and decision theory are tools anyone can learn to reason better.

2. IDEA 2 OF 6

   Think like a Bayesian

   Update beliefs in proportion to the strength of new evidence, starting from how likely something was before.

3. IDEA 3 OF 6

   Correlation isn't causation

   Before concluding A causes B, look for controlled comparisons and other explanations.

4. IDEA 4 OF 6

   Motivated reasoning

   People reason to protect identity.

   Create norms that reward changing your mind.

5. IDEA 5 OF 6

   Respect base rates

   Start with how common something is before considering vivid specifics.

6. IDEA 6 OF 6

   Rationality is a public good

   Institutions like science, courts and free speech help societies reason better than individuals.