Philosophy is the study of general and fundamental problems concerning matters such as existence, knowledge, values, reason, mind, and language.
Metaphysics is a branch of philosophy investigating the fundamental nature of being and the world that encompasses it.[1] Metaphysics attempts to answer two basic questions:
Ultimately, what is there?
What is it like?
Topics of metaphysical investigation include existence, objects and their properties, space and time, cause and effect, and possibility. A central branch of metaphysics is ontology, the investigation into the basic categories of being and how they relate to one other. Another central branch is metaphysical cosmology: which seeks to understand the origin and meaning of the universe by thought alone.
There are two broad conceptions about what “world” is studied by metaphysics. The strong, classical view assumes that the objects studied by metaphysics exist independently of any observer, so that the subject is the most fundamental of all sciences. The weaker, more modern view assumes that the objects studied by metaphysics exist inside the mind of an observer, so the subject becomes a form of introspection and conceptual analysis. Some philosophers, notably Kant, discuss both of these “worlds” and what can be inferred about each one.
Some philosophers and scientists, such as the logical positivists, reject the entire subject of metaphysics as meaningless, while others disagree and think that it is legitimate.
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Ontology is the philosophical study of the nature of being, becoming, existence or reality as well as the basic categories of being and their relations. Traditionally listed as a part of the major branch of philosophy known as metaphysics, ontology often deals with questions concerning what entities exist or may be said to exist and how such entities may be grouped, related within a hierarchy, and subdivided according to similarities and differences. Although ontology as a philosophical enterprise is highly theoretical, it also has practical application in information science and technology, such as ontology engineering.
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Logical positivism and logical empiricism, which together formed neopositivism, was a movement in Western philosophy that sought to legitimize philosophical discourse by placing it on a basis shared with empirical sciences’ best examples, such as Einstein’s general theory of relativity. Its central thesis was verificationism, a theory of knowledge which asserted that only statements verifiable through empirical observation are cognitively meaningful. Efforts to convert philosophy to this new scientific philosophy were intended to prevent confusion rooted in unclear language and unverifiable claims.[1] The Berlin Circle and the Vienna Circle—groups of philosophers, scientists, and mathematicians in Berlin and in Vienna—propounded logical positivism starting in the late 1920s.
Existentialism is a term applied to the work of certain late-19th- and 20th-century European philosophers who, despite profound doctrinal differences,[2][3][4] shared the belief that philosophical thinking begins with the human subject—not merely the thinking subject, but the acting, feeling, living human individual.[5] While the predominant value of existentialist thought is commonly acknowledged to be freedom, its primary virtue is authenticity.[6] In the view of the existentialist, the individual’s starting point is characterized by what has been called “the existential attitude”, or a sense of disorientation, confusion, or dread in the face of an apparently meaningless or absurd world.[7] Many existentialists have also regarded traditional systematic or academic philosophies, in both style and content, as too abstract and remote from concrete human experience.[8][9]
Soren Kierkegaard is generally considered to have been the first existentialist philosopher,[2][10][11] though he did not use the term existentialism.[12] He proposed that each individual—not society or religion—is solely responsible for giving meaning to life and living it passionately and sincerely, or “authentically”.[13][14] Existentialism became popular in the years following World War II, and strongly influenced many disciplines besides philosophy, including theology, drama, art, literature, and psychology.[15]
There has never been general agreement on the definition of existentialism. The term is often seen as a historical convenience as it was first applied to many philosophers in hindsight, long after they had died. In fact, while existentialism is generally considered to have originated with Kierkegaard, the first prominent existentialist philosopher to adopt the term as a self-description was Jean-Paul Sartre. Sartre posits the idea that “what all existentialists have in common is the fundamental doctrine that existence precedes essence”, as scholar Frederick Copleston explains.[16] According to philosopher Steven Crowell, defining existentialism has been relatively difficult, and he argues that it is better understood as a general approach used to reject certain systematic philosophies rather than as a systematic philosophy itself.[2] Sartre himself, in a lecture delivered in 1945, described existentialism as “the attempt to draw all the consequences from a position of consistent atheism.”[17]