This is a comprehensive introduction to the fundamentals of logic (both formal logic and critical reasoning), with exceptionally clear yet conversational explanations and a multitude of engaging examples and exercises. Herrick''s examples are on-point and fun, often bringing in real-life situations and popular culture. And more so than other logic textbooks, Introduction to Logic brings in the history of philosophy and logic through interesting boxes/sidebars and discussions, showing logic''s relation to philosophy. The book is especially suited for use in the "Open Course Library," a comprehensive online logic course that is open and free. Jointly funded by the state of Washington and the Bill & Melinda Gates Foundation, the Logic Course is one of 80 hybrid courses available online at no charge to the more than 400,000 students in the Washington system. The course is also available for logic courses throughout the US and the world. The Logic Course is available online now. Herrick was