Logic
College · Certificate available
267 lessons 2.3h runtime 9 units 353 links between lessons Test yourself · 9 quizzes, a mid exam, and a final
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Begin with Unit 1: Arguments & Validity. It sets the foundation for everything that follows.
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Unit 1: Arguments & Validity 31 lessons, 1 lecture part
Lecture: Watch · 30:49
- 001 What Logic Is
- 002 Statements
- 003 Non-Statements
- 004 Arguments
- 005 Premises
- 006 Conclusions
- 007 Indicator Words
- 008 Arguments vs. Non-Arguments
- 009 Explanations vs. Arguments
- 010 Standard Form
- 011 Validity
- 012 Invalidity
- 013 Validity Is About Form, Not Truth
- 014 Valid with False Premises
- 015 Invalid with All True Statements
- 016 Soundness
- 017 Valid vs. Sound
- 018 Deductive vs. Inductive
- 019 Inductive Strength
- 020 Cogency
- 021 The Counterexample Method
- 022 Testing Validity by Counterexample worked example
- 023 Enthymemes
- 024 The Principle of Charity
- 025 Argument Structure: Serial, Convergent, Linked
- 026 Diagramming an Argument worked example
- 027 Complex Passages: Sub-Conclusions
- 028 Truth, Validity, Soundness: The Map
- 029 Deciding Deductive vs. Inductive
- 030 Capstone: Full Passage Analysis review
- 031 Unit 1 Recap: The Skeleton
Unit 2: Language & Definition 20 lessons, 1 lecture part
Lecture: Watch · 21:44
- 041 Cognitive vs. Emotive Meaning
- 042 Ambiguity
- 043 Lexical vs. Syntactic Ambiguity
- 044 Vagueness
- 045 Ambiguity vs. Vagueness
- 046 Intension and Extension
- 047 Definiendum and Definiens
- 048 Stipulative Definitions
- 049 Lexical Definitions
- 050 Precising Definitions
- 051 Theoretical Definitions
- 052 Persuasive Definitions
- 053 Definition by Genus and Difference
- 054 Ostensive and Enumerative Definitions
- 055 Operational Definitions
- 056 Too Broad, Too Narrow
- 057 Circular Definitions
- 058 Evaluating a Definition worked example
- 059 Verbal vs. Factual Disputes
- 060 Capstone: Dissolving a Verbal Dispute review
Unit 3: Categorical Logic 40 lessons, 2 lecture parts
- 066 Categorical Statements
- 067 Subject and Predicate Terms
- 068 The Four Standard Forms
- 069 A Statements
- 070 E Statements
- 071 I Statements
- 072 O Statements
- 073 Quantity
- 074 Quality
- 075 Distribution
- 076 Distribution Across the Four Forms
- 077 Venn Diagrams for Statements
- 078 Diagramming All Four Forms worked example
- 079 Contradictories
- 080 Contraries
- 081 Subcontraries
- 082 Subalternation
- 083 Existential Import
- 084 Conversion
- 085 Obversion
- 086 Contraposition
- 087 Applying Immediate Inferences worked example
- 088 Translating into Standard Form
- 089 "Only" and "The Only"
- 090 Singular Statements
- 091 Translation Walkthrough worked example
- 092 The Categorical Syllogism
- 093 Major, Minor, and Middle Terms
- 094 Mood and Figure
- 095 Identifying Mood and Figure worked example
- 096 The Venn Test for Validity
- 097 Venn Test: Valid Case worked example
- 098 Venn Test: Invalid Case worked example
- 099 Rules Method: Distribution Rules
- 100 Rules Method: Quality Rules
- 101 The Existential Fallacy
- 102 Undistributed Middle
- 103 Illicit Major and Illicit Minor
- 104 Sorites
- 105 Capstone: Full Syllogism Analysis review
Unit 4: Propositional Logic 42 lessons, 2 lecture parts
- 116 Simple vs. Compound Statements
- 117 The Five Connectives
- 118 Negation
- 119 Conjunction
- 120 Disjunction
- 121 Exclusive "Or"
- 122 The Conditional
- 123 Antecedent and Consequent
- 124 The Biconditional
- 125 Translating "Unless"
- 126 Translating "Only If"
- 127 Necessary vs. Sufficient Conditions
- 128 "If" vs. "Only If"
- 129 Scope and the Main Connective
- 130 Symbolizing Compound Statements worked example
- 131 Truth Table: Negation
- 132 Truth Table: Conjunction
- 133 Truth Table: Disjunction
- 134 Truth Table: The Conditional
- 135 Why the Conditional's Table Looks Wrong
- 136 Truth Table: The Biconditional
- 137 Row Counts: 2ⁿ
- 138 Building a Full Truth Table worked example
- 139 Tautologies
- 140 Self-Contradictions
- 141 Contingent Statements
- 142 Logical Equivalence
- 143 Consistency
- 144 Testing Equivalence and Consistency worked example
- 145 The Truth-Table Test for Validity
- 146 Full Validity Test Walkthrough worked example
- 147 The Short Truth-Table Method
- 148 Short Method Walkthrough worked example
- 149 Modus Ponens
- 150 Affirming the Consequent
- 151 Modus Tollens
- 152 Denying the Antecedent
- 153 Hypothetical Syllogism
- 154 Disjunctive Syllogism
- 155 Affirming a Disjunct
- 156 Constructive Dilemma
- 157 Capstone: Form-Spotting Drill review
Unit 5: Natural Deduction 31 lessons, 1 lecture part
Lecture: Watch · 34:22
- 191 What a Proof Is
- 192 Proof Notation
- 193 Modus Ponens as a Proof Move
- 194 Modus Tollens as a Proof Move
- 195 Hypothetical Syllogism as a Proof Move
- 196 Disjunctive Syllogism as a Proof Move
- 197 Simplification
- 198 Conjunction
- 199 Addition
- 200 Constructive Dilemma as a Proof Move
- 201 First Proof Walkthrough worked example
- 202 Proof Strategy: Working Backward worked example
- 203 Replacement Rules: The Concept
- 204 De Morgan's Rules
- 205 Commutativity
- 206 Associativity
- 207 Distribution
- 208 Double Negation
- 209 Transposition
- 210 Material Implication
- 211 Material Equivalence
- 212 Exportation
- 213 Tautology (Redundancy)
- 214 Proof Using Replacement Rules worked example
- 215 Conditional Proof
- 216 Conditional Proof Walkthrough worked example
- 217 Indirect Proof
- 218 Indirect Proof Walkthrough worked example
- 219 Proving Tautologies
- 220 The Common Proof Errors
- 221 Capstone: A Mixed-Strategy Proof review
Unit 6: Predicate Logic 27 lessons, 1 lecture part
Lecture: Watch · 35:29
- 256 Why Propositional Logic Isn't Enough
- 257 Constants and Variables
- 258 Predicates
- 259 The Universal Quantifier
- 260 The Existential Quantifier
- 261 The Four Forms, Upgraded
- 262 Free vs. Bound Variables
- 263 The Pairing Rule
- 264 Translation Practice worked example
- 265 Quantifier Negation
- 266 Applying Quantifier Negation worked example
- 267 Universal Instantiation
- 268 Universal Generalization
- 269 Existential Instantiation
- 270 Existential Generalization
- 271 First Predicate Proof worked example
- 272 Proof with EI Restrictions worked example
- 273 Relational Predicates
- 274 Overlapping Quantifiers
- 275 Translating Relational Sentences
- 276 Identity
- 277 "Only," "Except," and Superlatives
- 278 Definite Descriptions
- 279 Relational Proof Walkthrough worked example
- 280 The Finite-Universe Method
- 281 Proving Invalidity worked example
- 282 Capstone: Full Predicate Analysis review
Unit 7: Induction & Probability 27 lessons, 1 lecture part
Lecture: Watch · 31:26
- 331 Strength Revisited
- 332 Enumerative Induction
- 333 Sample Size and Sample Bias
- 334 Argument from Analogy
- 335 What Makes Analogies Strong
- 336 Mill's Method of Agreement
- 337 Method of Difference
- 338 The Joint Method
- 339 Concomitant Variation
- 340 Method of Residues
- 341 Applying Mill's Methods worked example
- 342 Correlation vs. Causation
- 343 Necessary and Sufficient Causes
- 344 Three Interpretations of Probability
- 345 Conjunction: Independent Events
- 346 Conditional Probability
- 347 Disjunction Rules
- 348 The Negation Rule
- 349 Probability Walkthrough worked example
- 350 Base Rates
- 351 Bayes' Theorem
- 352 Bayes Worked Example worked example
- 353 The Gambler's Fallacy
- 354 Regression to the Mean
- 355 Abduction
- 356 What Makes an Explanation Best
- 357 Capstone: A Causal Claim in the Wild review
Unit 8: Fallacies 33 lessons, 1 lecture part
Lecture: Watch · 33:01
- 376 What Makes a Fallacy
- 377 Formal vs. Informal Fallacies
- 378 Ad Hominem, Abusive
- 379 Ad Hominem, Circumstantial
- 380 Tu Quoque
- 381 Appeal to Force
- 382 Appeal to Pity
- 383 Appeal to the People
- 384 Appeal to Unqualified Authority
- 385 Appeal to Ignorance
- 386 Hasty Generalization
- 387 Accident
- 388 Converse Accident
- 389 False Cause
- 390 Slippery Slope
- 391 Weak Analogy
- 392 Begging the Question
- 393 Complex Question
- 394 False Dichotomy
- 395 Suppressed Evidence
- 396 Equivocation
- 397 Amphiboly
- 398 Composition
- 399 Division
- 400 Straw Man
- 401 Red Herring
- 402 Missing the Point
- 403 Genetic Fallacy
- 404 Special Pleading
- 405 No True Scotsman
- 406 Loaded Language
- 407 A Method for Fallacy Identification worked example
- 408 Capstone: Fallacy Hunt review
Unit 9: Applied Argumentation (Capstone Strand) 16 lessons, 1 lecture part
Lecture: Watch · 25:14
- 426 The Reconstruction Pipeline
- 427 Charity Under Fire
- 428 Premise Acceptability
- 429 Burden of Proof
- 430 Rebuttals vs. Undercutters
- 431 Steelmanning
- 432 Mapping at Essay Scale
- 433 Full Reconstruction Walkthrough worked example
- 434 Statistical Claims in Media
- 435 Evaluating Expert Testimony
- 436 Motivated Reasoning, Structurally
- 437 Building Your Own Argument
- 438 Constructing a Deductive Argument worked example
- 439 Capstone: Full Essay Analysis review
- 440 Capstone: Construct and Defend review
- 441 The Map of Everything
Who this subject is for
- Philosophy, law and computing students
- Anyone preparing for reasoning-heavy exams
- Professionals who build or judge arguments
- Anyone who wants to think more clearly
Why Logic matters
Logic is the study of what follows from what, and every field that argues uses it. It is the foundation for:
- Philosophy
- Law and argument
- Mathematics and proofs
- Computer science
- Critical thinking
Time to complete
- of lessons (267, measured)
- 2.3 h
- of lectures (11)
- 5.1 h
- learning hours on the certificate, with quizzes and the final
- 11 h
Times are measured from the recordings and the exam time limits. Go at your own pace; nothing expires.
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