Epistemology, Critical Thinking, and Critical Thinking Pedagogy HARVEY SIEGEL Department of Philosophy University of Miami Coral Gables, FL 33124 U.S.A. ABSTRACT: To be a critical thinker is to base one's beliefs and actions on reasons. But the notions of 'reason' and 'rationality' are philosophically problematic. What is a reason? How do we tell that some consideration constitutes a reason for doing or believing something? By what criteria do we evaluate reasons? How are those criteria themselves evaluated? What is it for a belief or action to be justified? What is the relationship between justification and truth? These questions are epistemological questions; they are also relevant to critical thinking and its pedagogy. In this paper I argue (1) that critical thinking pre- supposes particular answers to contentious epistemological questions, i.e. that there is an epistemology underlying critical thinking; and (2) that these epistemological considerations are fundamental to an adequate understanding of critical thinking and should be explicitly treated in basic critical thinking courses. Epistemology is basic both to critical thinking and to its pedagogy. KEY WORDS: epistemology, critical thinking, pedagogy, reasons, rationality, justification, truth, relativism. Being a critical thinker requires basing one's beliefs and actions on reasons; it involves committing oneself to the dictates of rationality. The notions of 'reason' and 'rationality', however, are philosophically problem- atic. Just what is a reason? How do we know that some consideration constitutes a reason for believing or doing something? How do we evaluate the strength or merit of reasons? What is it for a belief or action to be justified? What is the relationship between justification and truth? Why is rationality to be valued? Questions such as these are central to epistemology. Because they are abstract and difficult, their relevance to education for critical thinking is not always appreciated. But so long as critical thinking is thought of as centrally involving reasons and rationality, these questions are basic to the critical thinking student's understanding of her subject matter. Without having some epistemological understanding of notions such as reason, rationality, knowledge, truth, evidence, warrant, justification, and so on, the critical thinking student has at best a superficial grasp of her subject. It is central to critical thinking education that students be given some understanding of the epistemology underlying critical thinking. Argumentation 3:127-140,1989. © 1989 KluwerAcademic Publishers. Printed in the Netherlands.