In
metaphysics (in particular,
ontology), the different kinds or ways of
being are called categories of being or simply categories. According to the
Aristotelian tradition, a being is anything that can be said to be in the various senses of this word. Hence, to investigate the categories of being is to determine the most fundamental senses in which things can be said to be. A category, more precisely, is any of the broadest
classes of things - 'thing' here meaning anything whatever that can be discussed and cannot be
reduced to any other class.
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