CROUSAZ, JEAN PIERRE DE (1663-1750), Swiss writer, was born at Lausanne. He was a many-sided man, whose numerous works on many subjects had a great vogue in their day, but are now forgotten. He has been described as an _initiateur plutôt qu'un créateur_, chiefly because he introduced at Lausanne the philosophy of Descartes in opposition to the reigning Aristotelianism, and also as a Calvinist pendant (for he was a pastor) of the French _abbés_ of the 18th century. He studied at Geneva, Leyden and Paris, before becoming (1700) professor of philosophy and mathematics at the academy of Lausanne, of which he was four times rector before 1724, when the theological disputes connected with the _Consensus_[1] led him to accept a chair of philosophy and mathematics at Groningen. In 1726 he was appointed governor to the young prince Frederick of Hesse-Cassel, and in 1735 returned to Lausanne with a good pension. In 1737 he was reinstated in his old chair, which he retained to his death. Gibbon, describing his first stay at Lausanne (1752-1755), writes in his _Autobiography_, "the logic of de Crousaz had prepared me to engage with his master Locke and his antagonist Bayle."
The most important of his works are: _Nouvel Essai de logique_ (1712), _Géométrie des lignes et des surfaces rectilignes et circulaires_ (1712), _Traité du beau_ (1714), _Examen du traité de la liberté de penser d'Antoine Collins_ (1718), _De l'éducation des enfants_ (1722, dedicated to the then Princess of Wales), _Examen du pyrrhonisme ancien et moderne_ (1733, an attack chiefly on Bayle), _Examen de l'essai de M. Pope sur l'homme_ (1737, an attack on the Leibnitzian theory of that poem), _Logique_ (6 vols., 1741), _De l'esprit humain_ (1741), and _Réflexions sur l'ouvrage intitulé: La Belle Wolfienne_ (1743). (W. A. B. C.)
[1] The "Consensus ecclesiarum Helveticarum reformatarum" was a document drawn up in 1675 and imposed in 1722--as a test of strict Protestant orthodoxy as to the doctrine of grace--by Bern on its subjects in Lausanne and Vaux.
CROW (Dutch, _kraai_, Ger. _Krähe_, Fr. _corbeau_, Lat. _corvus_), a name most commonly applied in Britain to the bird properly called a rook (_Corvus frugilegus_), but perhaps originally peculiar to its congener, nowadays usually distinguished as the black or carrion-crow (_C. corone_). By ornithologists it is also used in a far wider sense, as under the title crows, or _Corvidae_, is included a vast number of birds from almost all parts of the world, and this family is probably the most highly developed of the whole class _Aves_. Leaving out of account the best known of these, as the raven, rook, daw, pie and jay, with their immediate allies, our attention will here be confined to the crows in general; and then the species of the family to which the appellation is more strictly applicable may be briefly considered. All authorities admit that the family is very extensive, and is capable of being parted into several groups, but scarcely any two agree. Especially must reserve be exercised as regards the group _Streperinae_, or piping crows, belonging to the Australian Region, and referred by some writers to the shrikes (_Laniidae_): and the jays too have been erected into a distinct family (_Garrulidae_), though it seems hardly possible to separate them even as a subfamily from the pies (_Pica_ and its neighbours), which lead almost insensibly to the typical crows (_Corvinae_). Dismissing these subjects for the present, it will perhaps be most convenient to treat of the two groups which are represented by the genera _Pyrrhocorax_ or choughs, and _Corvus_ or true crows in the most limited sense.