Epistemology is the branch of philosophy that examines the nature, origin, and limits of knowledge. Also called theory of knowledge, it explores different types of knowledge, such as propositional knowledge about facts, practical knowledge in the form of skills, and knowledge by acquaintance as a familiarity through experience. Epistemologists study the concepts of belief, truth, and justification to understand the nature of knowledge. To discover how knowledge arises, they investigate sources of justification, such as perception, introspection, memory, reason, and testimony.
The philosophy of perception is concerned with the nature of perceptual experience and the status of perceptual data, in particular how they relate to beliefs about, or knowledge of, the world. Any explicit account of perception requires a commitment to one of a variety of ontological or metaphysical views. Philosophers distinguish internalist accounts, which assume that perceptions of objects, and knowledge or beliefs about them, are aspects of an individual's mind, and externalist accounts, which state that they constitute real aspects of the world external to the individual. The position of naïve realism—the 'everyday' impression of physical objects constituting what is perceived—is to some extent contradicted by the occurrence of perceptual illusions and hallucinations and the relativity of perceptual experience as well as certain insights in science. Realist conceptions include phenomenalism and direct and indirect realism. Anti-realist conceptions include idealism and skepticism. Recent philosophical work have expanded on the philosophical features of perception by going beyond the single paradigm of vision.
Skepticism, also spelled scepticism in British English, is a questioning attitude or doubt toward knowledge claims that are seen as mere belief or dogma. For example, if a person is skeptical about claims made by their government about an ongoing war then the person doubts that these claims are accurate. In such cases, skeptics normally recommend not disbelief but suspension of belief, i.e. maintaining a neutral attitude that neither affirms nor denies the claim. This attitude is often motivated by the impression that the available evidence is insufficient to support the claim. Formally, skepticism is a topic of interest in philosophy, particularly epistemology.
Social epistemology refers to a broad set of approaches that can be taken in epistemology that construes human knowledge as a collective achievement. Another way of characterizing social epistemology is as the evaluation of the social dimensions of knowledge or information.
Justification is a property of beliefs that fulfill certain norms about what a person should believe. Epistemologists often identify justification as a component of knowledge distinguishing it from mere true opinion. They study the reasons why someone holds a belief. Epistemologists are concerned with various features of belief, which include the ideas of warrant, knowledge, rationality, and probability, among others.
In epistemology, the regress argument is the argument that any proposition requires a justification. However, any justification itself requires support. This means that any proposition whatsoever can be endlessly (infinitely) questioned, resulting in infinite regress. It is a problem in epistemology and in any general situation where a statement has to be justified.
Philosophical skepticism is a family of philosophical views that question the possibility of knowledge. It differs from other forms of skepticism in that it even rejects very plausible knowledge claims that belong to basic common sense. Philosophical skeptics are often classified into two general categories: Those who deny all possibility of knowledge, and those who advocate for the suspension of judgment due to the inadequacy of evidence. This distinction is modeled after the differences between the Academic skeptics and the Pyrrhonian skeptics in ancient Greek philosophy. Pyrrhonian skepticism is a practice of suspending judgement, and skepticism in this sense is understood as a way of life that helps the practitioner achieve inner peace. Some types of philosophical skepticism reject all forms of knowledge while others limit this rejection to certain fields, for example, knowledge about moral doctrines or about the external world. Some theorists criticize philosophical skepticism based on the claim that it is a self-refuting idea since its proponents seem to claim to know that there is no knowledge. Other objections focus on its implausibility and distance from regular life.
Roderick Milton Chisholm was an American philosopher known for his work on epistemology, metaphysics, free will, value theory, deontology, deontic logic and the philosophy of perception.
Contextualism, also known as epistemic contextualism, is a family of views in philosophy which emphasize the context in which an action, utterance, or expression occurs. Proponents of contextualism argue that, in some important respect, the action, utterance, or expression can only be understood relative to that context. Contextualist views hold that philosophically controversial concepts, such as "meaning P", "knowing that P", "having a reason to A", and possibly even "being true" or "being right" only have meaning relative to a specified context. Other philosophers contend that context-dependence leads to complete relativism.
Virtue epistemology is a current philosophical approach to epistemology that stresses the importance of intellectual and specifically epistemic virtues. Virtue epistemology evaluates knowledge according to the properties of the persons who hold beliefs in addition to or instead of the properties of the propositions and beliefs. Some advocates of virtue epistemology also adhere to theories of virtue ethics, while others see only loose analogy between virtue in ethics and virtue in epistemology.
Philosophical realism – usually not treated as a position of its own but as a stance towards other subject matters – is the view that a certain kind of thing has mind-independent existence, i.e. that it exists even in the absence of any mind perceiving it or that its existence is not just a mere appearance in the eye of the beholder. This includes a number of positions within epistemology and metaphysics which express that a given thing instead exists independently of knowledge, thought, or understanding. This can apply to items such as the physical world, the past and future, other minds, and the self, though may also apply less directly to things such as universals, mathematical truths, moral truths, and thought itself. However, realism may also include various positions which instead reject metaphysical treatments of reality entirely.
Laurence BonJour is an American philosopher and Emeritus of Philosophy at the University of Washington.
Keith Lehrer is Emeritus Regent's Professor of philosophy at the University of Arizona and a research professor of philosophy at the University of Miami, where he spends half of each academic year.
Metaepistemology is the branch of epistemology and metaphilosophy that studies the underlying assumptions made in debates in epistemology, including those concerning the existence and authority of epistemic facts and reasons, the nature and aim of epistemology, and the methodology of epistemology.
Michael Williams is a British philosopher who is currently Krieger-Eisenhower Professor in the Department of Philosophy at Johns Hopkins University, noted especially for his work in epistemology.
The following outline is provided as an overview of and topical guide to epistemology:
Epistemology or theory of knowledge is the branch of philosophy concerned with the nature and scope (limitations) of knowledge. It addresses the questions "What is knowledge?", "How is knowledge acquired?", "What do people know?", "How do we know what we know?", and "Why do we know what we know?". Much of the debate in this field has focused on analyzing the nature of knowledge and how it relates to similar notions such as truth, belief, and justification. It also deals with the means of production of knowledge, as well as skepticism about different knowledge claims.
The KK thesis or KK principle is a principle of epistemic logic which states that "If you know that P is the case then you know that you know that P is the case." This means that one cannot know that P is, if one does not know whether one's knowledge of P is correct. Its application in science can be expressed in the way that it must not only justify its knowledge claims but it must also justify its method of justifying. The principle is also described as knowledge-reflexivity contention.
Gail Stine was an American philosopher who specialized in epistemology and philosophy of language. She was born in Schenectady, New York.
Jennifer. Nagel is a Canadian philosopher at the University of Toronto. Her research focuses on epistemology, philosophy of mind, and metacognition. She has also written on 17th century (Western) philosophy, especially John Locke and René Descartes.
