A category is an ordered set of predicates, produced by the activity of the intellect, arranged according to degree of generality from a most general genus concept (substance) down to a least general species concept (human being), passing through the intermediate levels of more or less general genus concepts (body, organism, animal). Above the categories are ‘transcendental’ concepts like being, which signify the items of more than one category and are, therefore, even more general than the concepts of any one category. Below the categories are individual concepts like this human being or Socrates that pick out one and only one thing.