Epistemologists are philosophers who study the nature, scope, and limits of knowledge. They explore questions such as "What is knowledge?" and "How do we acquire it?" Their work often involves analyzing different types of knowledge, including empirical knowledge gained through experience and a priori knowledge that is independent of experience. These thinkers also examine the justification of beliefs, focusing on how we can determine whether something is true or false. By investigating concepts like belief, truth, and justification, epistemologists contribute to our understanding of how we know what we know and the reliability of our knowledge sources.