Chapter 1: Introduction

The subject of formal logic is part philosophy, part mathematics and these days part computer science. It has essentially to do with reasoning and truth. It is based on a language designed to enable things to be said clearly and unambiguously, making it a vehicle for elucidation, analysis and rigorous foundations relevant to a wide range of other disciplines. In these notes, the emphasis is on the conceptual foundations of logic rather than on particular proof techniques and the like. Hence the best approach to learning logic from them is to seek to understand why things work the way they do rather than to memorise a lot of disconnected facts. Logic presents a unique mix of the utterly simple and the profound which makes it engrossing and beautiful. These notes are not bedtime stories: you can't read them with your brain in neutral. Take them at your own pace and enjoy the rewards.