Logic · 7 modules · 21 steps
Logic: How to Think Clearly
Reasoning as a skill you practise rather than a subject you read about. It moves from what an argument is, through fallacies and formal logic in both the Greek and the Indian traditions, into evidence, probability, causation, and finally the psychology of your own errors, which is where most bad reasoning actually comes from. The last module is the point of the first six. The promise is that you will be able to take an argument apart, say precisely why it fails, and notice when the argument is your own.
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What an Argument Is
Three short books on the basic unit. What premises and conclusions are, what makes an inference valid, and why clear thinking is a discipline rather than a talent.
A Rulebook for Arguments
Anthony WestonUnder a hundred pages of rules for making and assessing arguments. The most useful book per page on this entire site.
Premises, conclusions and the difference between deductive and inductive argument, in ten minutes.
Open companionThe standard textbook, kept here for its exercises. Logic is learned by doing the problems, and this is where the problems are.
The Philosopher's Toolkit
Julian Baggini and Peter S. FoslA reference of the moves: validity, soundness, necessary and sufficient conditions, begging the question, category mistakes. Look things up rather than reading it through.
Validity separated from truth, which is the distinction most people get wrong first.
Open companionBeing Logical
D.Q. McInernyMcInerny treats clear thinking as a habit built from attention, precision and honesty about what you actually know. Short, and closer to ethics than to mathematics.
Clear thinking presented as a trainable habit rather than an inherited gift.
Open companionFallacies and Persuasion
The catalogue of ways arguments go wrong, and the two-and-a-half-thousand-year-old account of how people are actually persuaded, which is not the same thing.
Thinking from A to Z
Nigel WarburtonAn alphabetical field guide to fallacies and rhetorical tricks, from ad hominem to the slippery slope. Dip into it and you will start hearing them everywhere.
The most frequent fallacies with real examples, which is what makes them stick.
Open companionAn Illustrated Book of Bad Arguments
Ali AlmossawiEach fallacy on one page with a drawing. It sounds slight and it is the fastest way to make the list memorable.
Fallacies identified in real recorded arguments, which is harder than spotting them on the page.
Open companionRhetoric
AristotleThe other half of the subject. Aristotle is describing how people are actually moved, which is by character and emotion at least as much as by proof.
The three appeals with modern examples, so you can see the ancient scheme still operating.
Open companionTwo Traditions of Formal Logic
Formal logic was invented twice, in Greece and in India, and the Indian version is almost never taught. Read both and the European one stops looking inevitable.
Logic: A Very Short Introduction
Graham PriestPriest covers validity, conditionals, modality, probability and paradox in a hundred and fifty pages, with puzzles. More demanding than it looks and worth it.
The syllogism explained from scratch, which is the foundation Priest builds on.
Open companionLogic Made Easy
Deborah J. BennettBennett's subject is why intelligent people fail simple logic problems, with the experimental evidence. It makes the formal rules feel necessary rather than pedantic.
The Wason selection task and what it shows about how badly conditionals are handled.
Open companionClassical Indian Philosophy
Peter Adamson and Jonardon GaneriRead the chapters on Nyaya, which built a theory of inference, perception and debate independently of Aristotle and with a different structure.
A university lecture placing Nyaya among the Indian schools and explaining what it took as valid knowledge.
Open companionEvidence and Induction
The hardest problem in the subject. Nothing you have ever observed guarantees anything about tomorrow, and science works anyway. Three attempts to explain why.
An Enquiry concerning Human Understanding
David HumeRead sections four to seven. Hume shows that induction has no rational justification, and then carries on reasoning inductively, which is the honest position.
Open the core textHume's argument reconstructed step by step, including the sceptical solution he settles for.
Open companionWhat Is This Thing Called Science?
Alan F. ChalmersThe standard undergraduate introduction to the philosophy of science, moving through induction, falsification, Kuhn and beyond without requiring any of it in advance.
How scientific reasoning is supposed to work and the points at which it does not.
Open companionConjectures and Refutations
Karl PopperPopper's answer: stop trying to confirm things and try to refute them instead. Read the first essay on science and pseudoscience, which is where the criterion appears.
Falsifiability explained with the examples Popper himself used, including astrology and Marxism.
Open companionChance
Most of the reasoning you do about the world is probabilistic whether you know it or not. Three books that make the intuitions less wrong.
The Drunkard's Walk
Leonard MlodinowHow randomness governs far more than people believe, and how consistently we invent explanations for noise. The chapter on the hot hand is worth the book.
What randomness actually means, which turns out to be a harder question than it sounds.
Open companionNaked Statistics
Charles WheelanStatistics without the formulae: what a mean hides, what a correlation is, why the sample matters more than the size. Written to be read rather than studied.
Open the core textThe core statistical ideas in one sitting, which pairs directly with Wheelan's chapters.
Open companionThinking in Bets
Annie DukeA professional poker player on separating the quality of a decision from the quality of its outcome. The single most useful correction in this pathway.
Duke on why judging decisions by their results is the mistake almost everyone makes.
Open companionCause and Correlation
The gap between what the data shows and what somebody claims it shows. One book on the mathematics of causation and two on the everyday abuse of it.
The Book of Why
Judea Pearl and Dana MackenziePearl's causal ladder, from seeing to doing to imagining, and the argument that statistics deliberately refused to talk about causes for a century.
The confusion demonstrated with examples, which is the problem Pearl set out to solve properly.
Open companionCalling Bullshit
Carl T. Bergstrom and Jevin D. WestTwo professors on how to spot misleading numbers, selection effects and bad data visualisation. Grew out of a course they taught for exactly this.
The authors opening their own course, with their working definition of the thing.
Open companionHow to Lie with Statistics
Darrell HuffFrom 1954 and still accurate, because the tricks have not changed: truncated axes, chosen averages, unstated base rates. A hundred and forty small pages.
The classic tricks shown on real charts, which is faster than reading about them.
Open companionThinking Under Uncertainty
The final module and the reason for the other six. All the logic in the world does not help if the reasoning that needs checking is your own.
Thinking, Fast and Slow
Daniel KahnemanThe two systems, and the long catalogue of biases that follows. Long, and worth reading slowly enough that you start catching yourself.
Open the core textThe biases Kahneman catalogued, shown operating, with the pattern-finding habit they come from.
Open companionSuperforecasting
Philip E. Tetlock and Dan GardnerTetlock ran a tournament to find out who predicts well and what they do differently. The answer is unglamorous: small updates, numerical estimates, no ideology.
The forecasting tournament and the habits that separated the best forecasters from the experts.
Open companionThe Scout Mindset
Julia GalefGalef's distinction between defending a position and seeing what is there. The practical companion to everything else in this pathway.
Galef's soldier and scout distinction, which is the book in eleven minutes.
Open companion