CATANZA`RO (20), a city in Calabria, 6 m. from the Gulf of Squillace, with an old castle of Robert Guiscard.

CATEGORICAL IMPERATIVE, Kant’s name for the self-derived moral law, “universal and binding on every rational will, a commandment of the autonomous, one and universal reason.”

CATEGORIES are either classes under which all our Notions of things may be grouped, or classes under which all our Thoughts of things may be grouped; the former called Logical, we owe to Aristotle, and the latter called Metaphysical, we owe to Kant.  The Logical, so derived, that group our notions, are ten in number:  Substance or Being, Quantity, Quality, Relation, Place, Time, Position, Possession, Action, Passion.  The Metaphysical, so derived, that group our thoughts, are twelve in number:  (1) as regards quantity, Totality, Plurality, Unity; (2) as regards quality, Reality, Negation, Limitation; (3) as regards relation, Substance, Accident, Cause and Effect, Action and Reaction; (4) as regards modality, Possibility and Impossibility, Existence and Nonexistence, Necessity and Contingency.  John Stuart Mill resolves the categories into five, Existence, Co-existence, Succession, Causation, and Resemblance.

CATESBY, MARK, an English naturalist and traveller, wrote a natural history of Carolina, Florida, and the Bahamas (1680-1750).

CATESBY, ROBERT, born in Northamptonshire, a Catholic of good birth; concerned in the famous Gunpowder Plot; shot dead three days after its discovery by officers sent to arrest him (1573-1605).

CATH`ARI, OR CATHARISTS, i. e. purists or puritans, a sect of presumably Gnostic derivation, scattered here and there under different names over the S. and W. of Europe during the Middle Ages, who held the Manichaean doctrine of the radically sinful nature of the flesh, and the necessity of mortifying all its desires and affections to attain purity of soul.

CATHARINE, ST., OF ALEXANDRIA, a virgin who, in 307, suffered martyrdom after torture on the wheel, which has since borne her name; is represented in art as in a vision presented to Christ by His Mother as her sole husband, who gives her a ring.  Festival, Nov. 25.

CATHARINE I., wife of Peter the Great and empress of Russia, daughter of a Livonian peasant; “a little stumpy body, very brown,... strangely chased about from the bottom to the top of the world,... had once been a kitchen wench”; married first to a Swedish dragoon, became afterwards the mistress of Prince Menschikoff, and then of Peter the Great, who eventually married her; succeeded him as empress, with Menschikoff as minister; for a time ruled well, but in the end gave herself up to dissipation, and died (1682-1727).