ENCYCLICAL LETTERS. 60 ENCYCLOPAEDIA. of a council to all the churches, or by a bishop to all the churches of a particular district or diocese, were so called; but the term is now ap- plied exclusively to letters addressed by the Pope to all the bishops of the Roman Catholic Church, which usually contain injunctions and warnings linst dangers which may threaten the Church. One of the most remarkable encyclicals was that issued !>y Pius IX. in 1804 accompanied by a syllabus in which he condemned eighty alleged errors in modern ideas of religion and civiliza- tion. Hi- successor, Pope Leo XIII., i--ued a number of them on such subjects as socialism, Bible study, capital and labor, and the reunion of Christendom. ENCYCLOPEDIA (Gk. eyKVKXtnraiSfta, en- di "i. a barbarous derivative of the Greek phrase iynAicKun iroi5ei«, enkyklios paideia, cir- cular, complete education). Originally, the entire group of studies which every free-born Greek youth was required to complete in prepara- tion for active life; the liberal curriculum. In this sense the Greek phrase was adopted by the Romans. Its signification, however, was early widened, both in Greek and Roman usage, to in- clude systematic study of, or instruction in, all the branches of learning — of the entire 'circle' of the arts and sciences, or of a special group of them; and this remained its dominant mean- ing until a comparatively recent time. At pres- ent it survives only in the technical use of the word in systematic theology and philosophy to designate the investigati f the relations of the various special subjects which those disciplines include. With this idea of 'encyclic' education was also soon associated the notion "f collecting the materials of such instruction into a sin work, in which the contents and relations of the various arts and sciences should systematically b expounded. Attempts to produce books of this kind were made at an early date, though the name 'encyclopaedia' was no! given to them until the sixteenth century. This is now its common appli- eal ion. What has been said of the origin of the word explain- also the distinguishing characteristic of the earliest encyclopaedias. They wen- trea- tisi "i groups of connected treatises adapted for continuoui reading and study, and no! mere rep- ertories of knowledge. They were designed to i i ill comprehensii e ti I i i ban as worl "i rel rence in the modern sense of phraser. And t In ir Bubstanc resp led to theii form, for they contained, for the most pari . simply the mo ten ivi ao nmula- tion ' rning made by (heir authors indi- vidually, ami bore no resemblance to the product i native scholarship « hich i he entei prise of the i lern publisher has made familiar. This type "i encyclopaedia, with various modifications, prevailed for many centuries, and has ool entirely been abandoned. The firs) i^ -aid to bav< mpiled by Bpeu sippus i died b i Plato, but .,i in- work in I hi lini Vmong the Rom Marcus Tercntiu Varro (died about B.C. 27) t he i" i of tii i d in /' M i ine Books of Studie - 1 exem pliflea well the above-explained connection of the i lopaedia with the libi ral curriculum. It was an ei i la "i i lie liberal art- grammar, dialectii rhetoric, geometry, arithmet ic, astrolo i architecture in nini ! - - each devoted to one of these special subjects. His Antiquitates Rerum Humcmarum et Divi- narum, in forty-one books, dealing with Roman antiquities, civil ami religious, was of a similar character. Neither of these works has survived. The famous Historia Naturalis of Pliny the Elder (A.n. 23-79), the earliest of the encyclo- pedic compilations of antiquity which we pos- approaches nearer to modern works of the kind in material, but in form does not differ es- sentially from its predecessors. It is an en- cyclopaedia of natural science, considered espe- cially with reference to human life, and, accord- ingly, including geography, medicine, and the history of art. The topics treated in its thirty- seven books comprise the mathematical and physical description of the world, anthropology and human physiology, zoology, comparative anat- omy and physiology, botany (including agricul- ture and horticulture), medicinal zoology, and mineralogy (together with the use of the metals and of precious stones in the arts) . It is a mass of facts, often ill digested, collected from a large variety of sources, and is an inexhaustible store- bouse of information. About four and a half centuries later Martianus Capella, a native of North Africa — probably of Carthage — composed an encyclopaedia of the seven liberal arts, which in the Middle Ages was extensively used as a text-book in the schools, and which departs even further than those above mentioned from the modern ideal. It is partly in prose and partly in verse, resembling in this the Sat lira Menippea of Varro and the Satyricon of Petronius; hence the names Satura and Satyricon have been given to it. Satura (satire) personified is also rep- resented by the author as having inspired the work. Its theme is the marriage of Mercury with ' a very learned maiden' (doctissima virgo) , Philologia (philology), on the advice of Apollo, and the various forms of learning (personified) are introduced in the bridegroom's train. Though • Hue highly esteemed, it is now notable chiefly from the fact that in it the revolution of the planet- Mercury and Venus about the sun, and not about the earth, is asserted in a passage which may have suggested to Copernicus his theory of planetary motions. A work in twenty books (unfinished), entitled Btymologiarum [Origynum) Libri V., with a similar aim. was compiled by Isidore, Bishop of Seville (about 570-636). It deals with the seven liberal arts, medicine, animals, the earth, Old Testament antiquities, etc.. and was long deservedly held in high repute. The tenth book, which is etymo- logical in contents, is arranged alphabetically. I id '- encyclopaedia was rearranged in twenty- two books, and otherwise edited in the ninth cen- tury, under the title De Universe Libri XXII., swe • Opua (also known as /)<• Xiilimi Rerum, De Origins Rerum, etc.), by another ec- tic,Rabanus (or Srabanus) Maurus (c.776- 866), Archbishop of Mainz. Much of Isidore's material was omitted, and Rabanus'a work as e whole shows no advance bey. .ml thai of bis lecessor. From about the middle of the elew m h cent urj dates a short encyclopaedic work in Greek, written in the form of ques- tions and answei bj Michael Constantinus Psel- i"- He younger (born 1020, died after 1105). entitled AtffatricaXfa mnTi'SuTr^. It treats of divinity, natural history, and various special topics, mure important Creek work, prob-
