The systematic study of the form of valid inference and the most general laws of truth is known as logic. The situation where there is a definite relation of logical support between the inference and its conclusion is called a valid inference. The scope of logic includes classification of arguments, study of proof and inference, and the study of semantics and syntax. There are several types of logic such as syllogistic logic, propositional logic, predicate logic, and modal logic. The process of evaluation where logic is used to analyze facts and thereby form a judgment is known as critical thinking. This book aims to shed light on some of the unexplored aspects of logic and critical thinking. It is meant for students who are looking for an elaborate reference text on logic and critical thinking. Coherent flow of topics, student-friendly language and extensive use of examples make this book an invaluable source of knowledge.