H+ (Plus) A New Religion?

The Art of Loving

Parallel Thinking

Inward

Six Frames: For Thinking About Information

The Devil's Notebook

How to Have Creative Ideas: 62 exercises to develop the mind

Leaves of Grass

Serious Creativity: How to be creative under pressure and turn ideas into action

Logically Fallacious: The Ultimate Collection of Over 300 Logical Fallacies (Academic Edition)

Five-Day Course in Thinking

The Philosopher's Book of Questions & Answers: Questions to Open Your Mind

How To Have A Beautiful Mind

How to Win Every Argument: The Use and Abuse of Logic, Edition 2

Lateral Thinking: An Introduction

The World As I See It

The Mechanism of Mind: Understand how your mind works to maximise memory and creative potential

Teach Yourself To Think

An Illustrated Book of Bad Arguments: Learn the Lost Art of Making Sense (Bad Arguments)