Critical thinking is usually taught as a list of things to avoid, which is why most people finish the list and reason exactly as before. It is better understood as three separable questions asked in order. Is this argument *shaped* correctly — do the premises, if true, actually support the conclusion? Are the premises *true* — and how would I find out? And am *I* the thing distorting the answer? Chapters D and A are the first question, C and F the second, B and E the third. The order matters: a beautifully evidenced argument with a broken shape proves nothing, and a well-shaped argument built on a rumour proves nothing either. Read for the three questions; the named terms are just labels for where each one fails.
Each chapter opens with the short version. Tap one to read the detail.
Fallacies are relevance failures, not rudeness
~2 min
A fallacy is not a rude argument or a wrong conclusion — it is a move where the support offered does not bear on the claim. Naming one is only useful if you can say which link is missing, and the same sentence can be a fallacy in one context and a fair point in another.
Biases are systematic, and knowing about them barely helps
~2 min
Cognitive biases are not random errors or stupidity — they are predictable, directional distortions produced by fast mental shortcuts that are usually efficient. Crucially, knowing a bias by name does almost nothing to stop it, which is why the remedies are procedural rather than mental.
Every evidence claim is a hidden comparison
~2 min
Statistics in arguments almost never fail at the arithmetic. They fail at the comparison: what was this group compared against, and could that comparison group differ in some other way that explains the result?
Separate the shape of an argument from its contents
~2 min
An argument's form and its truth are independent, and confusing them causes most bad reasoning about reasoning. A perfectly valid argument can reach a false conclusion, and a true conclusion can arrive through a broken one.
Judge decisions by what was knowable, not by how they turned out
~2 min
A good decision and a good outcome are different things, and conflating them destroys your ability to learn. Under uncertainty the only fair standard is the information and reasoning available at the time.
Go sideways, not down
~2 min
Faced with an unfamiliar source, the instinct is to read it closely and judge it on how it looks. Professional fact-checkers do the opposite: they leave the page almost immediately and find out what independent sources say about it.
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