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 studies 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?".
, also known as direct realism
or common sense realism
, is a common sense theory
"Naïve realism claims that the world is pretty much as common sense would have it. All objects are composed of matter, they occupy space, and have properties such as size, shape, texture, smell, taste and colour. These properties are usually perceived correctly. So, when we look at and touch things we see and feel those things directly, and so perceive them as they really are. Objects continue to obey the laws of physics and retain all their properties whether or not there is anyone present to observe them doing so."
In contrast, indirect or representative realism claims that we are directly aware only of internal representations of the external world, as objects are hidden behind a "veil of perception". Idealism, on the other hand, asserts that no world exists apart from mind-dependent ideas.
Robert Nozick (November 16, 1938 – January 23, 2002) was an American philosopher and Pellegrino University Professor at Harvard University. Nozick, schooled at Columbia, Oxford and Princeton, was a prominent American political philosopher in the 1970s and 1980s. He did additional but less influential work in such subjects as decision theory and epistemology. His Anarchy, State, and Utopia (1974) was a libertarian answer to John Rawls' A Theory of Justice, published in 1971. He was born in Brooklyn, the son of a Jewish entrepreneur from Russia. He was married to the American poet Gjertrud Schnackenberg. Nozick died in 2002 after a prolonged struggle with cancer. His remains are interred at Mount Auburn Cemetery in Cambridge, Massachusetts.