Semantic Aspects of Propositional Logic

For a 60-year-old engaging with 'Semantic Aspects of Propositional Logic', the goal is to provide a robust, self-paced, and interactive learning experience that fosters cognitive maintenance and deep conceptual understanding. 'Language, Proof and Logic' by Barwise & Etchemendy is selected as the best-in-class tool worldwide due to its unparalleled integration of a comprehensive textbook with powerful interactive software (Fitch, Tarski's World, Boole). This combination allows for a multi-modal approach to learning: the textbook provides rigorous theoretical grounding in propositional semantics (truth values, truth tables, logical consequence, satisfiability, validity, consistency), while the software enables immediate, hands-on application and visualization of these abstract concepts.

Implementation Protocol for a 60-year-old:

1. Initial Setup & Familiarization: Start by installing the bundled software on a comfortable computer setup. Spend the first week familiarizing oneself with Fitch (for natural deduction proof construction), Tarski's World (for building semantic models), and Boole (for truth table construction). Watch introductory tutorials for each component. This hands-on, low-stakes exploration prevents initial intimidation.
2. Structured Self-Paced Learning: Follow the textbook's chapters sequentially, paying particular attention to the sections on propositional logic (chapters 1-8 are highly relevant for semantics). After reading a section, immediately apply the concepts using the corresponding software exercises. For instance, after learning about truth tables, use Boole to construct them; after understanding logical consequence, use Tarski's World to build models that demonstrate satisfiability or unsatisfiability.
3. Active Engagement & Problem Solving: Do not passively read. Work through every exercise in the book and software. Use a dedicated notebook to jot down thoughts, draw diagrams, and work through proofs by hand before verifying with the software. This active engagement is crucial for solidifying neural pathways and enhancing memory retention at this age.
4. Regular, Moderate Sessions: Instead of long, infrequent study blocks, engage in shorter (e.g., 45-90 minute) daily or every-other-day sessions. This optimizes cognitive absorption and prevents fatigue, making learning sustainable and enjoyable.
5. Review and Reflection: Periodically review earlier chapters and exercises. Discuss challenging concepts with others (if a study group is available) or write reflective summaries of key semantic ideas. This metacognitive practice deepens understanding and reinforces learning, supporting cognitive agility and critical reasoning skills vital at this developmental stage.