Existence has been variously defined by sources. In common usage, it is the world one is aware or conscious of through one's senses, and that persists independently in one's absence. Other definitions describe it as everything that 'is', or more simply, everything. Some define it to be everything that most people believe in. Aristotle relates the concept to causality.
Ontology is the philosophical study of the nature of being, existence or reality in general, as well as of the basic categories of being and their relations. Traditionally listed as a part of the major branch of philosophy known as metaphysics, ontology deals with questions concerning what entities exist or can be said to exist, and how such entities can be grouped, related within a hierarchy, and subdivided according to similarities and differences. A lively debate continues about the existence of God.
Epistemology studies criteria of truth, defining "primary truths" inherently accepted in the investigation of knowledge. The first is existence. It is inherent in every analysis. Its self-evident, a priori nature cannot be consistently doubted, since a person objecting to existence according to some standard of proof must implicitly accept the standard's existence as a premise.
Materialism holds that the only thing that exists is matter, that all things are composed of material, and all phenomena (including consciousness) are the result of material interactions.
Life is a characteristic that distinguishes objects that have self-sustaining biological processes from those that do not – either because such functions have ceased (death), or else because they lack such functions and are classified as "inanimate".
Read more about Existence: Etymology, Historical Conceptions, Predicative Nature, Modern Approaches, Dharmic "middle Way" View
Famous quotes containing the word existence:
“I consider, then, the power to annul a law of the United States, assumed by one state, incompatible with the existence of the Union, contradicted expressly by the letter of the Constitution, unauthorized by its spirit, inconsistent with every principle on which it was founded, and destructive of the great object for which it was formed.”
—Andrew Jackson (1767–1845)
“We go on dating from Cold Fridays and Great Snows; but a little colder Friday, or greater snow would put a period to man’s existence on the globe.”
—Henry David Thoreau (1817–1862)
“To call a posit a posit is not to patronize it. A posit can be unavoidable except at the cost of other no less artificial expedients. Everything to which we concede existence is a posit from the standpoint of a description of the theory-building process, and simultaneously real from the standpoint of the theory that is being built.”
—Willard Van Orman Quine (b. 1908)