Thinking books · Critical thinking · Carl Bergstrom & Jevin West, 2020
Calling Bullshit — the big ideas
How to detect misleading claims, especially numerical and graphical ones, without being a specialist.
Free — no account needed to read
The big ideas
You rarely need to understand the internals of a study to spot a problem: checking the sample, the comparison group, the denominator and who is missing catches most of it.
Selection effects explain an enormous share of surprising findings — who got into the data in the first place often produces the result on its own.
Graphs mislead through axis choices, cherry-picked ranges and misleading area, and doing so requires no false numbers at all.
The asymmetry: producing a misleading claim is far cheaper than refuting one, which is why fixed checks beat case-by-case effort.
Practise it — no need to have read it
Take a statistic you saw this week. Ask: what is the denominator, who is not in the sample, and compared with what?
A hint: Most misleading claims fail on one of those three before you need any statistics.
Where it shows up in real life
- Reading research or news
- Evaluating a product claim
- Reviewing your own dashboard
Described in our own words with the source named — never quoted, and not a substitute for reading the book.
Thinking methods from this book
- The six-question claim check — A fixed pass over any claim before you act on it.
The thinking it builds
- Critical Thinking — Evaluate claims and evidence
- Logical Thinking — Reason consistently