Epistemology ( ( listen); from Greek ἐπιστήμη, epistēmē, meaning 'knowledge', and λόγος, logos, meaning 'logical discourse') is the branch of philosophy concerned with the theory of knowledge.
Epistemology is the study of the nature of knowledge, justification, and the rationality of belief. Much debate in epistemology centers on four areas: (1) the philosophical analysis of the nature of knowledge and how it relates to such concepts as truth, belief, and justification, (2) various problems of skepticism, (3) the sources and scope of knowledge and justified belief, and (4) the criteria for knowledge and justification. Epistemology addresses such questions as: "What makes justified beliefs justified?", "What does it mean to say that we know something?", and fundamentally "How do we know that we know?".
The Gettier problem is considered a fundamental problem in modern epistemology or first-order logic, issuing from counter-examples to the definition of knowledge as justified true belief, and dealing extensively with the concept of justified true belief (JTB), and the scope of the concept of JTB, as well as those attacks upon JTB which Gettier exemplars introduce. The problem owes its name to a three-page paper published in 1963, by Edmund Gettier, called "Is Justified True Belief Knowledge?", in which Gettier argues that this is not necessarily the case. Many or most analytic philosophers would wish to be able to hold to what is known as the JTB account of knowledge: the claim that knowledge can be conceptually analyzed as justified true belief — which is to say that the meaning of sentences such as "Smith knows that it rained today" can be given with the following set of necessary and jointly sufficient conditions:
A subject S knows that a proposition P is true if, and only if:
- P is true
- S believes that P is true, and
- S is justified in believing that P
Alvin Ira Goldman (born 1938) is an American professor of Philosophy at Rutgers University in New Jersey. He previously taught at the University of Michigan and at the University of Arizona. He earned his PhD from Princeton University and is married to Holly Smith, a well known ethicist, former administrator, and current professor at Rutgers University. He has done influential work on a wide range of philosophical topics, but his principal areas of research are epistemology, philosophy of mind, and cognitive science.
Goldman's early book, A Theory of Human Action (a revised version of his Ph.D. thesis), presents a systematic way of classifying and relating the many actions we perform at any time. Its influence was broad and can be found in, among other writings, John Rawls' book A Theory of Justice. Goldman's early work in action theory soon gave way to work in other branches of philosophy, most influentially epistemology.