'Correlation  does not imply causation.' For decades, this mantra was invoked by scientists in order to avoid taking positions as to whether one thing  caused another, such as smoking and cancer, or carbon dioxide and global  warming. But today, that taboo is dead. The causal revolution, sparked  by world-renowned computer scientist Judea Pearl and his colleagues, has  cut through a century of confusion and placed cause and effect on a  firm scientific basis. Now, Pearl and science journalist Dana Mackenzie explain causal thinking to general readers for the first time, showing  how it allows us to explore the world that is and the worlds that could  have been. It is the essence of human and artificial intelligence. And  just as Pearl's discoveries have enabled machines to think better, The  Book of Why explains how we too can think better.