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Tier III · Quid sequitur?

Dialectic

117 lessons
Begin lesson 1

What follows from what. Categorical syllogisms, the difference between validity, truth, and soundness, necessary and sufficient conditions, the formal fallacies, and the discipline of stating an opponent’s case fairly before answering it.

Unit 1 · Valid, True, and Sound

  1. Valid, True, and SoundNot started · 10 minBegin
  2. A Valid Argument With False PremisesNot started · 9 minBegin
  3. An Invalid Argument With a True ConclusionNot started · 9 minBegin
  4. Soundness Is Two QuestionsNot started · 9 minBegin
  5. Refuting by CounterexampleNot started · 10 minBegin
  6. Two Kinds of SupportNot started · 8 minBegin

Unit 2 · The Categorical Proposition

  1. PropositionNot started · 8 minBegin
  2. Subject, Copula, PredicateNot started · 9 minBegin
  3. QuantityNot started · 9 minBegin
  4. QualityNot started · 8 minBegin
  5. The Four FormsNot started · 9 minBegin
  6. Putting a Sentence Into Standard FormNot started · 10 minBegin

Unit 3 · Distribution and Existential Import

  1. What Distribution MeansNot started · 9 minBegin
  2. Distribution in A and ENot started · 9 minBegin
  3. Distribution in I and ONot started · 10 minBegin
  4. Existential ImportNot started · 10 minBegin

Unit 4 · The Square of Opposition

  1. The Four CornersNot started · 9 minBegin
  2. ContradictoriesNot started · 9 minBegin
  3. ContrariesNot started · 9 minBegin
  4. SubcontrariesNot started · 9 minBegin
  5. SubalternationNot started · 10 minBegin

Unit 5 · Immediate Inferences

  1. An Inference From One PremiseNot started · 9 minBegin
  2. ConversionNot started · 10 minBegin
  3. ObversionNot started · 9 minBegin
  4. ContrapositionNot started · 10 minBegin
  5. Which Moves Preserve TruthNot started · 10 minBegin
  6. Logical EquivalenceNot started · 9 minBegin

Unit 6 · The Parts of a Syllogism

  1. Three Terms, Three PropositionsNot started · 8 minBegin
  2. Major, Minor, and MiddleNot started · 9 minBegin
  3. Standard FormNot started · 9 minBegin
  4. FigureNot started · 9 minBegin
  5. MoodNot started · 9 minBegin

Unit 7 · The Rules of the Syllogism

  1. Six Rules, One TestNot started · 10 minBegin
  2. Exactly Three TermsNot started · 9 minBegin
  3. The Middle Term Must Be DistributedNot started · 10 minBegin
  4. Illicit ProcessNot started · 10 minBegin
  5. The Negative RulesNot started · 9 minBegin
  6. The Existential FallacyNot started · 10 minBegin
  7. Testing a SyllogismNot started · 10 minBegin

Unit 8 · Venn Diagrams

  1. Two CirclesNot started · 9 minBegin
  2. Three CirclesNot started · 10 minBegin
  3. Reading Validity Off the DiagramNot started · 10 minBegin

Unit 9 · Converse, Inverse, Contrapositive

  1. Antecedent and ConsequentNot started · 8 minBegin
  2. The ConverseNot started · 9 minBegin
  3. The InverseNot started · 9 minBegin
  4. The ContrapositiveNot started · 10 minBegin
  5. Which Rearrangement Keeps the TruthNot started · 9 minBegin

Unit 10 · Necessary, Sufficient, and Both

  1. A Condition Without Which NotNot started · 8 minBegin
  2. A Condition That Is EnoughNot started · 8 minBegin
  3. Telling the Two Apart in Ordinary ProseNot started · 9 minBegin
  4. Both at OnceNot started · 9 minBegin

Unit 11 · Arguments From a Conditional

  1. Modus PonensNot started · 9 minBegin
  2. Modus TollensNot started · 10 minBegin
  3. The Chain ArgumentNot started · 9 minBegin
  4. Either–OrNot started · 9 minBegin
  5. Two Senses of "Or"Not started · 10 minBegin

Unit 12 · Formal Fallacies

  1. Affirming the ConsequentNot started · 10 minBegin
  2. Denying the Antecedent, On Its OwnNot started · 10 minBegin
  3. Affirming a DisjunctNot started · 9 minBegin
  4. Valid or NotNot started · 10 minBegin

Unit 13 · The Dilemma

  1. The Shape of a DilemmaNot started · 9 minBegin
  2. The Constructive DilemmaNot started · 9 minBegin
  3. The Destructive DilemmaNot started · 9 minBegin
  4. Three Ways to Answer OneNot started · 10 minBegin

Unit 14 · The Enthymeme and the Sorites

  1. The Argument With a Piece MissingNot started · 9 minBegin
  2. Supplying the Unstated PremiseNot started · 10 minBegin
  3. Judging a Completed EnthymemeNot started · 10 minBegin
  4. The SoritesNot started · 10 minBegin

Unit 15 · Definition

  1. What a Definition HasNot started · 9 minBegin
  2. Genus and DifferentiaNot started · 9 minBegin
  3. Extension and IntensionNot started · 9 minBegin
  4. Too Broad, Too Narrow, CircularNot started · 10 minBegin
  5. Obscure, and Needlessly NegativeNot started · 10 minBegin
  6. The Five PredicablesNot started · 9 minBegin

Unit 16 · Kinds of Definition

  1. Five KindsNot started · 10 minBegin
  2. Vagueness and AmbiguityNot started · 9 minBegin
  3. The Persuasive DefinitionNot started · 10 minBegin
  4. Which Kind Is This?Not started · 10 minBegin
  5. The Verbal DisputeNot started · 9 minBegin

Unit 17 · Fallacies of Relevance

  1. Missing the PointNot started · 9 minBegin
  2. The Red HerringNot started · 8 minBegin
  3. Three Ad HominemsNot started · 10 minBegin
  4. Poisoning the WellNot started · 8 minBegin
  5. The Genetic FallacyNot started · 8 minBegin
  6. Appeal to Authority, Well and BadlyNot started · 10 minBegin
  7. The Latin NamesNot started · 10 minBegin

Unit 18 · Fallacies of Presumption

  1. Assuming What You Set Out to ProveNot started · 9 minBegin
  2. The Loaded QuestionNot started · 8 minBegin
  3. False DilemmaNot started · 9 minBegin
  4. Accident and Converse AccidentNot started · 9 minBegin
  5. A Part Is Not the WholeNot started · 9 minBegin
  6. Which Presumption Was Made?Not started · 10 minBegin

Unit 19 · False Cause, and the Claim That Cannot Lose

  1. After Is Not BecauseNot started · 9 minBegin
  2. False Cause More BroadlyNot started · 9 minBegin
  3. The Slippery SlopeNot started · 9 minBegin
  4. Special PleadingNot started · 8 minBegin
  5. Moving the Goalposts, and No True ScotsmanNot started · 9 minBegin

Unit 20 · Fallacies of Ambiguity

  1. EquivocationNot started · 9 minBegin
  2. AmphibolyNot started · 8 minBegin
  3. AccentNot started · 8 minBegin
  4. HypostatizationNot started · 8 minBegin
  5. The Fallacy of the BeardNot started · 9 minBegin

Unit 21 · Burden of Proof and Presumption

  1. Who Has to Make the CaseNot started · 8 minBegin
  2. PresumptionNot started · 8 minBegin
  3. The Status QuoNot started · 9 minBegin
  4. Prove Me WrongNot started · 9 minBegin
  5. Locating the Burden in a Real DisputeNot started · 10 minBegin

Unit 22 · Charity and Refutation

  1. The Principle of CharityNot started · 9 minBegin
  2. Direct RefutationNot started · 9 minBegin
  3. Indirect RefutationNot started · 9 minBegin
  4. Reductio ad AbsurdumNot started · 9 minBegin
  5. Conceding Without SurrenderingNot started · 9 minBegin

Unit 23 · Cross-Examination and the Elenchus

  1. What Cross-Examination Is ForNot started · 8 minBegin
  2. The Closed QuestionNot started · 8 minBegin
  3. Securing a Commitment and Using ItNot started · 9 minBegin
  4. The Question That Traps and the Question That ClarifiesNot started · 9 minBegin
  5. The Socratic ElenchusNot started · 10 minBegin