Whether you're studying on your own, teaching your own children, running a co-op class, or just tired of not being able to name what's wrong with a bad argument, Philalethic Logic gives you a practical, learnable system for telling sound reasoning from sophistry — in your own thinking, in the news, and in conversation with the people you love.

It's built to be applied, not just studied: a practical symbolic system with a consistent validation method carried all the way through, worked examples at every step, and an informal fallacy woven into nearly every chapter so the abstract and the everyday stay connected. Read as much of it as you like below before deciding what, if anything, to buy.

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Read For the Love of Truth Online — Chapter by Chapter

The Preface, Chapters 1–3, and A Final Word are open to everyone. Chapters 4–14 open up with a free account. The complete text, plus the Technical Reference, comes with Membership.

• PrefaceUnlocked for Everyone
• Chapter 1: Introduction to Philalethic LogicUnlocked for Everyone
• Chapter 2: Simple Ideas, Clauses, and SymbolsUnlocked for Everyone
• Chapter 3: Discrete, Indeterminate, and Portional ClaimsUnlocked for Everyone
• Chapter 4: Universal Claims, Existence, and DirectionFree and Paid Members
• Chapter 5: Negating ClaimsFree and Paid Members
• Chapter 6: Restating Negated ClaimsFree and Paid Members
• Chapter 7: Visualizing Categories and RelationshipsFree and Paid Members
• Chapter 8: Implication and InferenceFree and Paid Members
• Chapter 9: Validity, Soundness, and the Anatomy of an ArgumentFree and Paid Members
• Chapter 10: Contradiction: The Engine of ValidationFree and Paid Members
• Chapter 11: The Validation ProcessFree and Paid Members
• Chapter 12: Decomposition Rules, Constraints, and Branch MaturityFree and Paid Members
• Chapter 13: Worked Truth-Tree Validations I: Basic Clause ArgumentsFree and Paid Members
• Chapter 14: Worked Truth-Tree Validations IIFree and Paid Members
• Chapter 15: Direct Modal Claims: Necessity, Potential, and ContingencyPaid Members Only
• Chapter 16: Compound ClaimsPaid Members Only
• Chapter 17: Compound Claims and Successive Modal InspectionPaid Members Only
• Chapter 18: Handled Compound ClaimsPaid Members Only
• A Final WordUnlocked for Everyone
• Appendix A: Philalethic Logic Quick ReferencePaid Members Only
• Appendix B: Informal-Fallacy ReferencePaid Members Only
• Appendix C: Common Errors and TroubleshootingPaid Members Only
• GlossaryPaid Members Only
• IndexPaid Members Only
• Formal and Technical Reference (Working Draft 0.18)Paid Members Only

• For the Love of Truth (Main Text)Paid Members Only
• Teacher & Parent SupplementPaid Members Only
• Student WorkbookPaid Members Only
• Student Workbook Answer KeyPaid Members Only