MEPX
Chapter 3 of 10All chapters
  1. 1What it actually is
  2. 2Reading a claim
  3. 3Weighing evidence
  4. 4Judging sources
  5. 5Your own thumb on the scale
  6. 6Claims with numbers
  7. 7Cause and effect
  8. 8Persuasion techniques
  9. 9Information online
  10. 10Building the habit

Chapter 3 of 10

Weighing evidence

Not all support is equal.

A rough hierarchy

Systematic reviews and replicated trials sit at the top, single studies below, expert opinion below that, and anecdote at the bottom. The hierarchy is about how easily each is fooled.

  • A single striking study is a hypothesis, not a finding.
  • Extraordinary claims need evidence proportional to how surprising they are.

Anecdote

Stories are memorable and personal, which is why one testimonial outweighs a table of numbers in our judgement. Notice that pull rather than pretending you are immune to it.