JACQUES
266
JACQUIER
Going to Belgium, he taught privately at Mens and
Brussels, and in 1818 was appointed professor of the
French language and literature in the University of
Louvain. The Revolution of 1S30 allowed him to re-
turn to France. He went first to Valenciennes, and in
1838 to Paris, endeavouring to propagate his method
of teaching, and working for "the intellectual eman-
cipation " of his fellow-men. His works under the
common title of " Enseignement Universel" are:
"Langue maternelle" (Louvain, 1822); "Langues
toangeres" (Louvain, 1824); "Musique, Dessin et
Peinture" (Louvain, 1824); " Math^matiques " (Lou-
vain, 1828); "Droit et philosophic panccastique "
(Paris, 1839). He also wrote many articles in the
"Journal de I'emancipation intellectuelle ", published
by his two sons (1829-42), who also edited his "Me-
langes posthumes" (Paris, 1841). When Jacotot be-
gan to teach at Louvain, he knew neither Flemish nor
Dutch, while many of his pupils could not understand
French. To overcome this difficulty he gave them
both the French text and the Dutch translation of
Ffeelon's "T^lemaque". They were to memorize
some sentences of the French and carefully compare
them with the Dutch, every day repeating what they
knew and adding a little more. After some time Jaco-
tot was surprised at their progress, for with no other
help they had mastered the rules of spelling and gram-
mar and could apply them correctly. Encouraged by
this success, Jacotot thought he had found a universal
method and adapted it to all branches of knowledge.
This method rightly recognizes the necessity of the
student's own efforts and mental work, and it also en-
deavours to apply the principle that all knowledge is
so connected that to know one thing well, i. e. to know
it in all its connexions, supplies the key to a more per-
fect and extensive knowledge of other subjects also.
Hence it matters little where the student begins, or
what book he uses, provided he proceeds rightly.
Generally, instead of starting with the first elements,
Jacotot would have him begin with something com-
plex, which the student himself would analyze into its
elements — comparing these, noting their similarities
and differences, and thus finding the rules for himself.
Among the ninnber of principles which sum up Jaco-
tot's method, we may mention the following: "Know
sometliing well, and always refer everj^thing else to
that". " Everyone can be liis own master ". "Every-
body can teach, and teach even what he does not
know ". More paradoxical are the two axioms which
are given as the bases of the whole method : "All men
are of equal intelligence ", that is, are equally capable
of learning; "All is in all ", that is, the same general
ideas are found in every work, and consequently man
should strive to master one thing well and refer every-
thing to what he knows already. However exagger-
ated such principles, and even the whole method, may
seem, and however vehement at times Jacotot may
have been in defending them, it must be conceded that
they emphasize a few vital points, the necessity of
personal effort and application on the part of the
student, the connexion more or less immediate of all
ideas, the need of order and method, and the impor-
tance of thoroughness in knowledge.
GuiLLAHD in NouvcUe Biogrnphie ocnt'rale (Paris. 1858), s. v.; Klahr in Rein. E-ncyklopiidischea Handbuch der Piidagogik, IV ( Langensalza, 1905), 597: Perez in Buihson, Didionnaire de pedagoaie, II, i (Paris, 1888), 1399; Q01CK, Esmya on Educa- tional Reformer!) CSew York, 1904); Raumer, Gesch. der Pdda- gogik. Ill (Gutersich, 1897), 74.
C. A. DUBRAY.
Jacques de Vitry , historian of the crusades, cardinal. Bishop of Acre, later of Tusculum, b. at Vitry-sur- Keine, near Paris, probably about 1160; d. at Rome, 1240. After attending the University of Paris, then in its infanc.v, he visited Marie d'Oigiiies, a mystic of the Diocese of Liege, attracted by her reputation for holiness. On her advice he became a canon
regular, returned to Paris for ordination to the
priesthood, and thereafter devoted himself to preach-
ing; from 1210 to 1213 he was one of the most noted
preachers of the crusade against the Albigenses. In
fact so great was his renown throughout Christendom
that the Latin clergy of St. John of Acre chose him as
their bishop. He accepted the episcopal dignity with
the approbation of Honorius IIL From Palestine he
went to Egypt and was present at the capture of
Damietta (1218-20), an account of which he wrote to
the pope. The leaders of the crusade complained of
his imperious temper and attributed their reverses to
his stubbornness. In 1227 he returned to Rome but
soon resumed the offensive against the heretics of the
Diocese of Liege. In 1229 Gregory IX allowed him
to resign the See of Acre, created him a cardinal and
Bishop of Tusculum, and later legate in France and
in Germany. He did not long survive his refusal of
the Patriarchate of Jerusalem; at his request his
body was conveyed to Oignies.
Among his works are letters to Pope Honorius, which form an important source of the history of the Egyptian crusade (ed. Rohrich. "Zeitschrift fur Kirchengesch. ", XIV-XVI); a collection of sermon- models for the use of preachers; a " Liber de mulieri- bus Leodiensibus ", the most celebrated of these being Marie d'Oignies, whose wonderful visions the author relates (ed. Acta SS., June, IV, 630, 666), finally the "Historia Orientalis seu Hierosolymitana", his prin- cipal work, an account, atjirst hand, of the conditions in the Holy Land in the thirteenth century. He was of an inquiring and observant mind and conceived the plan — a remarkable one for the age in which he lived — of WTiting a geographical description of Palestine.
The first book is wholly devoted to that land and gives its history from the time of Mohammed ; describ- ing the expansion of Islam, he gives many picturesque details concerning Oriental idolaters, the Turcomans, the Bedouins, and especially the Assassins, subjects of the Old Man of the Mountain. His account of the crusades is followed by praise for the fertility of Palestine under Christian domination, and for the efforts of the Italians, French, Germans, Bretons, and English to colonize it. He likewise dwells upon the characteristics of the various indigenous nations and of the "PuUani", half-breeds, to whose vices he attributes the reverses of the Christians. The WTiter then undertakes a regular description of the physical geography of the country, and gives a great many particulars, half real and half fabulous, regarding its climate, flora, fauna, minerals, its barbarous and extraordinary nations, the Amazons, etc. The honey gathered from the reeds {ex calamcllis) was, of course, only cane sugar. A still more curious ac- count is that which he gives of the magnetic compass: " Acus ferrea postquam adamantem contigerit, ad stel- 1am septentrionalem, quae velut axis firmamenti aliis vergentibus non movetur, semper convertitur. L^nde valde necessaria est navigantibus in mari. " (Bon- gars, "Gesta Dei", I, 1106.) The remainder of the book is a history of the Kingdom of Jerusalem. Book II, a dismally painted picture of the Christians of the East, cluses with an account of the monastic orders and the hierarchy of Palestine. A third book, the story of the Egyptian crusade, is not from Jacques de Vitry, but from the pen of Oliver the Scholastic, Bishop of Paderborn.
Historia orientalis, ed. BoN<iAR.s, Gesta Dei per Francos, I, 1047-1145; French tr. in Gdizot's Collerlion des mimoires, XXII: Daunou, Jacques de Vitrif {Ilistoire Itltcraire de la France), XVIII (1835); Barroux, Jacques de Vitry (Paris, 1885).
Loins Brehier.
Jacquier, Francois, French mathematician and physicist, b. at Vitry-le-Francois, 7 June, 1711; d. at Home, 3 July, 1788. His early education was entrusted to an ecclesiastic, who soon recognized in
