Being

Being is an extremely broad concept encompassing objective and subjective features of reality and existence. Anything that partakes in being is also called a "being", though often this use is limited to entities that have subjectivity (as in the expression "human being"). So broad a notion has, inevitably, been elusive and controversial in the history of philosophy, beginning in western philosophy with attempts among the pre-Socratics to deploy it intelligibly.

As an example of efforts in recent times, Martin Heidegger (who himself drew on ancient Greek sources) adopted German terms like Dasein to articulate the topic. Several modern approaches build on such continental European exemplars as Heidegger, and apply metaphysical results to the understanding of human psychology and the human condition generally (notably in the Existentialist tradition).

By contrast, in mainstream Analytical philosophy the topic is more confined to abstract investigation, in the work of such influential theorists as W. V. O. Quine, to name one of many. One most fundamental question that continues to exercise philosophers is put by William James: "How comes the world to be here at all instead of the nonentity which might be imagined in its place? ... from nothing to being there is no logical bridge."

The deficit of such a bridge was first encountered in history by the Pre-Socratic philosophers during the process of evolving a classification of all beings (noun). Aristotle, who wrote after the Pre-Socratics, applies the term category (perhaps not originally) to ten highest-level classes. They comprise one category of substance (ousiae) existing independently (man, tree) and nine categories of accidents, which can only exist in something else (time, place). In Aristotle, substances are to be clarified by stating their definition: a note expressing a larger class (the genus) followed by further notes expressing specific differences (differentiae) within the class. The substance so defined was a species. For example, the species, man, may be defined as an animal (genus) that is rational (difference). As the difference is potential within the genus; that is, an animal may or may not be rational, the difference is not identical to, and may be distinct from, the genus.

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