Logic

That's Maths

Introducing Infinity

Maths in Bite-sized Chunks

The Mathematical Works of Lewis Carroll

Mathematical Thinking – For People Who Hate Math

Simply Gödel

Simply Turing

Introduction to Mathematical Philosophy

Equations from God

Foundations of Mathematical Thought: The Language of Numbers

Development Theory

Mastering Logical Reasoning

The Canterbury Puzzles, and Other Curious Problems

The Game of Logic