Book excerpt: 'Everything he writes is an enlightening education in how to be human.' - Elizabeth Day That Little Voice in Your Head is the practical guide to retraining your brain for optimal joy by Mo Gawdat, the internationally bestselling author of Solve for Happy. Mo reveals how by beating negative self-talk, we can change our thought processes, turning our greed into generosity, our apathy into compassion and investing in our own happiness. To fix a machine, first you need to find out what's wrong with it. To fix unhappiness, you need to find out what causes it. This book provides readers with exercises to help reshape their mental processes. Drawing on his expertise in programming and his knowledge of neuroscience, Mo explains how - despite their incredible complexity - our brains behave in ways that are largely predictable. From these insights, he delivers this user manual for happiness. Inspired by the life of his late son, Ali, Mo Gawdat has set out to share a model for happiness based on generosity and empathy towards ourselves and others. Using his experience as a former Google engineer and Chief Business Officer, Mo shares his 'code' for reprogramming our brain and moving away from the misconceptions modern life gives us.