Logic

• Why is Continuity in Topology defined 'Backwards'?
• Are Logically Alien Beings Possible? Descartes, Kant, Frege, and the Tractus
• Stone Spaces and the Compactness Theorem
• Quantifier Elimination
• Robinson, Craig, and Beth's Theorems
• Homomorphisms, Embeddings, and Elementary Embeddings
• Infinite Prisoner Hat Problem
• The Łoś-Tarski Preservation Theorem
• Completeness Theorem and Löwenheim-Skolem Theorem
• Modal Logic
• On Existential Quantification in Modal Contexts — Quine and Frege
• Temporal Logic
• Ramsey Numbers and the Infinite Ramsey Theorem
• Can the Mind Be Reduced to a Machine: Gödel's Disjunction and the Penrose-Lucas Argument
• Arithmetic Hierarchy
• Defining Gödel Numbers in Peano Arithmetic via the Beta Function
• Łoś's Theorem
• Fréchet Filters and Nonstandard Natural Numbers