Metaphysics refers generally to one of two similar but distinct uses of the term. In general, Metaphysics is the study of that which is beyond the physical or scientific, and includes the study of the origin of all things, morality, the underlying nature of all existence, causality, the nature of objects and the nature of personhood. The second, loosely associated use, is from the nutty, wooish New Age that co-opted the term for all things "spiritual" and "mystical" and "cool".
One particularly amusing explication of this difference is the disclaimer given by Professor Ron Amundson, a philosophy professor at the University of Hawaii, warning that the metaphysics course offered by his department is to do with things like free will and mind-and-body and that those interested in ESP, auras and astrology should drop the course because they'll fail.
The First Philosophy, Metaphysics was a pairing of his other seminal work, "Physics". One is a tract on science and the natural world, the other is a study and exploration of what can't be known by science or natural exploration, but that which comes from questions and reflections, and indeed intuition. Aristotle's work on metaphysics was in three parts: Ontology, or the study of existence and personhood (being); Natural Theology, the study of god, gods, and things "supernatual"; and Universal Science, building blocks for logic and scientific reasoning.
- ↑ As philosophy develops and expands over time, many of these subjects lumped by the Greeks into "metaphysics" become fully fleshed out philosophical disciplines in and of themselves