The Machine in the Ghost is the third book contained in the ebook Rationality: From AI to Zombies, by Eliezer Yudkowsky. It covers topics related to cognition, concepts, and the general notion of goal-oriented behavior.

The Machine in the Ghost contains three sequences of thematically connected essays, plus the stand-alone essay An Intuitive Explanation of Bayes's Theorem. These are all collected in the Rationality: From AI to Zombies ebook, but the essay names below also link to the original blog posts.