This book brings together essays by one of the pre-eminent scholars of informal logic.

Part I. Theorizing about Reasoning and Argument: 1. Informal logic and the theory of reasoning; 2. An historical approach to the study of argumentation; 3. Methodological problems in empirical logic; 4. Two empirical approaches to the study of reasoning; 5. Critical thinking, critical reasoning, and methodological reflection; Part II. Fallacies and Asymmetries: 6. Fallacies and the evaluation of reasoning; 7. Six types of fallaciousness; 8. Asymmetries in argumentation and evaluation; 9. The positive versus the negative evaluation of arguments; Part III. Critiques: 10. Siegel on critical thinking; 11. Introduction and intuition in the normative study of reasoning; 12. Logic, politics, and Gramsci; 13. The dialectical approach to interpretation and evaluation; 14. The Port-royal logic's theory of argument; 15. A critique of the dialectical approach; 16. Valid Ad Hominem arguments in philosophy; 17 Dialectics, evaluation, and argument; Part IV. Historical Analyses: 18. The concept of Ad Hominen argument in Galileo and Locke; 19. Newton's third rule of philosophizing; 20. Logic and rhetoric in Lavoisier's sealed note; 21. The concept of judgment and Huygens' theory of gravity; 22. Empiricism, judgment, and argument; 23. Criticism, reasoning, and judgment in science.