This book is an introduction of the Theory of Granular Causality as it exists in natural language discourse. Although the phenomenon of granular causality is very common in discourse, there has been very limited work for understanding it, and no work done to extract such relations from discourse. This book shows that there is a simple mechanism for capturing granular causality relations from text, and describes mechanisms for using granular causality for discovering all types of causal relations in text. The book also describes numerous real world applications of using a hierarchical (granular) causality, and provides important evidence that humans understand granular causality as easily as sequential causality.