**LOGIC MATTERS BLOG** Peter Smith’s occasional blog posts on logic, music, and other enthusiasms. Most recent posts ‘Tim Button on set theory’ (Nov 20); ‘Piranese, not Piranese’ (Nov 23); ‘The revised Study Guide — Modal logics’ (Nov 28).

**INTRO TO FORMAL LOGIC**. A corrected version of the second edition of *An Introduction to Formal Logic* is freely available here. There are also links to answers to exercises and to various supplementary materials.

**GÖDEL’S THEOREMS**. Two books are freely available here, *An Introduction to Gödel’s Theorems* and the much shorter *Gödel Without (Too Many) Tears*, along with related materials.

**CATEGORY THEORY** Links to resources at an introductory/intermediate level, including lecture notes and freely available books. Also a link to my currently stalled but hopefully evolving *Gentle Introduction* to categories.

**TEACH YOURSELF LOGIC** You will find here the much-downloaded, and still developing, *Study Guide* for beginning mathematical logic, as well as other resources (including Book Notes reviewing many texts)

**VARIA** Links to various papers. Also links to snippets from over a hundred notes on logic for (more or less) beginners. Plus my old but still occasionally recommended advice on writing papers!

**LaTeX FOR LOGICIANS** Pages pointing to a wide range of resources of interest to logicians, philosophers and others using LaTeX.