Metaphysic

Metaphysics is a branch of philosophy investigating the fundamental nature of being and the world that encompasses it. Metaphysics attempts to answer two basic questions:

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 another. 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.

Ontology deals with the determination whether categories of being are fundamental and discusses in what sense the items in those categories may be said to "be". It is the inquiry into being in so much as it is being ("being qua being"), or into beings insofar as they exist—and not insofar as (for instance) particular facts may be obtained about them or particular properties belong to them.

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