a person who proposes to resolve cases of conscience. Escobar has made a collection of the opinions of all the casuists before him. M. Le Fèvre, preceptor of Louis XIII., called the books of the casuists the art of quibbling with God; which does not seem far from truth, by reason of the multitude of distinctions and subtleties they abound withal. Mayer has published a bibliotheca of casuists, containing an account of all the writers on cases of conscience, ranged under three heads, the first comprehending the Lutheran, the second the Calvinist, and the third the Romish, casuists.

CASUSTRY, the doctrine and science of conscience and its cases, with the rules and principles of resolving the same; drawn partly from natural reason or equity; partly from authority of scripture, the canon law, councils, fathers, &c. To causality belongs the decision of all difficulties arising about what a man may lawfully do or not do; what is sin or not sin; what things a man is obliged to do in order to discharge his duty, and what he may let alone without breach of it.