This book presents a groundbreaking and surprising scientific investigation into how the mind works, how the brain works and what this means for why candidates win and lose elections. Since the 18th century, the idea of mind that has captured the imagination of philosophers, cognitive scientists, economists and political scientists is of a dispassionate mind that makes decisions by weighing evidence and reasoning to make the most valid conclusions. It bears no relation to how the mind and brain actually work. In this landmark book, Professor Drew Westen - a scientist and psychologist who has led a pioneering investigation into how the brain processes political information - shows through a whirlwind tour of American political leaders how electorates vote not with their heads, but with their hearts. He finds that Americans are a nation of passionate voters, not cool political spectators - they love (or hate) Bill Clinton and George W Bush. No-one else will do. The book, which examines data across several Presidential elections from the 1950s to the present day, is a serious and groundbreaking investigation into the role of emotion in driving voting behaviour.