## What is Logic?

This is the homepage of my draft textbook, *What is Logic?*, as well as a repository of resources for my students taking PHIL1031 Introduction to Logic or PHIL3201 Formal & Philosophical Logic at Durham University. The DRAFT status of this book is very important: Portions of it are substantially incomplete. If, however, you find any errors, please let me know.

#### Recent updates:

- 2018-03-09: Uploaded draft 2018-03-09; this version adds more informal explanation for the proof rules in Section 8.6.
- 2018-03-01: Uploaded draft 2018-03-01; this version says a bit about the substitution of constants, and uniformises some notation in Section 8.6

*Omnia disce, videbis postea nihil esse superfluum* |

--Hugh of S. Victor |

This page was last updated 09 March 2018.