LESIEUR-DÉSAULNIERS, ISAAC-STANISLAS (he signed Isaac Désaulniers), priest, professor, and superior of the Séminaire de Saint-Hyacinthe; b. 27 Nov. 1811 at Sainte-Anne-d’Yamachiche, Lower Canada, son of François Lesieur-Désaulniers, farmer and member of the assembly, and Charlotte Rivard-Dufresne; d. 22 April 1868 at Saint-Hyacinthe.
During his classical studies at the Séminaire de Nicolet, Isaac-Stanislas Lesieur-Désaulniers came in contact with Lamennais’s philosophy of certitude grounded in the general reason of mankind, or common consent, communicated by revelation and tradition. Désaulniers became a priest in 1829. He was immediately appointed professor of sciences (1829–33), then of philosophy (1831–33), at the Séminaire de Saint-Hyacinthe, where Lamennais’s ideas fired his colleagues Jean-Charles Prince*, Joseph-Sabin Raymond*, and Joseph La Rocque* with enthusiasm; they in turn were supported by Bishop Jean-Jacques Lartigue*, administrator at Montreal of the diocese of Quebec.
Conscious of the importance of intellectual exchange and concerned with the excellence of “his” seminary, Bishop Lartigue sent Désaulniers to the Jesuit university at Georgetown (Washington, D.C.), to study science and English, “without neglecting theology.” Désaulniers and his brother François, who was well regarded as a professor of science and philosophy at the Séminaire de Nicolet, were the first French Canadian clerics to undertake advanced study abroad. Désaulniers stayed at Georgetown from June 1833 to July 1834, studying science and familiarizing himself further with Lamennais’s philosophy of common consent, which was probably taught according to Jean-Marie Doney’s Nouveaux éléments de philosophie. . . . He returned to Saint-Hyacinthe with a “tinge of democratic liberalism,” just when the controversy (October 1833-September 1834) between Abbé Jacques Odelin*, a Cartesian, and the professors of the seminary, fervent supporters of Lamennais, had been ended by the encyclical Singulari nos of Gregory XVI, which condemned Lamennais’s Paroles d’un croyant. Profoundly discouraged, Désaulniers taught physics (1834–39, 1844–47), as well as returning to philosophy (1837–49), which he taught with the aid of the eclectic manual by Abbé Jérôme Demers* of the Séminaire de Québec. Demers was resolutely opposed to Lamennais, did not take common consent as a criterion of certainty, and showed himself more distinctly Cartesian in his treatment of the problem of ideas.
Désaulniers had been ordained on 30 July 1837, and because of his “determined, independent character” was requested to “be on his guard” during the disturbances of 1837–38; moreover, with his colleagues, he signed a statement justifying the teaching at the seminary, and guaranteeing that “moral philosophy” was taught in orthodox fashion according to the “fundamental principles of society” and “the duties of the citizen with regard to the government.”
Like a fair number of clerics of the time, Désaulniers contributed to the “popular press”; he argued polemically about scientific questions in La Minerve in 1837 (on the identification of a celestial body), and in the new Mélanges religieux in 1841 (on the safety of lightning conductors). Increasingly absorbed in the life of the seminary, he introduced the teaching of agricultural chemistry, and also of political economy (1845), and taught theology (1847–52). In 1847 he became “a beggar going from presbytery to presbytery” to collect the funds needed to build a new seminary.
Désaulniers was able to undertake a voyage in Europe and the Near East (16 Aug. 1852–28 March 1854) through the generosity of the family of Louis-François-Roderick (Rodrigue) Masson*, a seminary pupil for whom he was to act as guide. This voyage shaped his subsequent thinking and conduct. Already acquainted with the eastern United States, Désaulniers now discovered France, Italy, Austria, Germany, Switzerland, Belgium, Spain, Greece, Turkey, Palestine, Malta, and England. He visited the physical laboratories and libraries of many colleges and universities. In France, he went “first to the office of L’Univers,” then met the philosopher Pierre-Célestin Roux-Lavergne, Father Auguste Gratry, Abbé Théodore Combalot, as well as a son of Louis-Gabriel-Ambroise de Bonald and a grandson of Joseph de Maistre. His Italian tour led to Rome, the “centre of the world,” where he met Father Giovanni Perone and visited the universities. St Thomas Aquinas was virtually omnipresent: Désaulniers saw his manuscripts, his room, and his crucifix at Rome and Naples. Before returning from this pilgrimage to the fountainhead, he was appointed superior of the seminary (1853); he was to hold this office with no teaching duties until 1860. He was absent again only when, at the request of Bishop Ignace Bourget*, he was in Illinois (November 1856-June 185.7), and attempted in vain to bring around his former friend, the “schismatic” Charles-Paschal-Télesphore Chiniquy*.
Désaulniers once again taught philosophy from 1860 to 1868. After “wandering” from Cartesianism to eclectic philosophy by way of Lamennais’s philosophy of common consent, he had become a fervent adherent of the philosophy of St Thomas Aquinas, which he had discovered during his voyage in Europe and probably studied deeply during his term as superior. He read, translated, and taught the doctrines of the Doctor angelicus; in lectures given in the Cabinet de Lecture of the parish of Montreal and before the Union Catholique of Saint-Hyacinthe, he spread the “truth” of St Thomas’ word as it related to the history of philosophy, to the origin of knowledge, to authority, capital punishment, and the theory of power.
Released from his duties as superior, Désaulniers collaborated with his confrère Joseph-Sabin Raymond in the anti-liberal offensive of the day. He promoted the venture of the papal zouaves of the “militant” and soon “triumphant” church. He preached in honour of the defenders of the Holy See who had fallen at Mentana and Castelfidardo, and gave lectures on Rome and the Holy Land. He outlined a bishop’s duties on the occasion of the consecration of Bishop Charles La Rocque*, and expressed approval of the writings of Bishop Louis-François Laflèche* at the time of his consecration. Désaulniers became vicar general in 1866, and supported Raymond in a controversy with liberal Louis-Antoine Dessaulles* by criticizing in April 1867 a lecture given by the latter in 1863 on “progress.” Désaulniers died on 22 April 1868 and was buried at Saint-Hyacinthe, where numerous “persons of note” gathered for the occasion.
The philosophical development of this learned priest of Saint-Hyacinthe is to a certain extent representative of the pattern of Lamennais’s influence in Quebec; through his travels Désaulniers discovered Thomism as a truth, some 25 years after the condemnation of Lamennais and the standardization of eclectic philosophy by means of the “manual” of Abbé Demers had together left a philosophical void. Around 1860, when clerical authority was growing in Canada and elsewhere, this independent and determined scholar, who initially had commented in public only on purely scientific matters, turned increasingly towards an anti-liberal conservative proselytism. A cleric and professor of philosophy, his knowledge was his power.
ACAM, RLB, 1, pp.50, 216; 2, p.160; RLL, 7, pp.48, 107–8, 301–2, 467, 492; 8, pp.176, 321; 9, pp.69, 227; 901.009, 837–3. ASQ, mss, 626, p.26. ASSH, A, F, Grands cahiers, I, 97–99, 125f.; III, 2f., 8; IV, 19f., 48f., 58, 74–79, 97f., 108, 123–27; A, G, Correspondance des supérieurs, 1860–70, chemises 177, 187; Fonds Isaac Désaulniers; A, M, Lettres d’affaires, B, 127f. BUM, Coll. Baby, Corr. générale, lettre de J. Désaulniers, 24 avril 1859. PAC, MG 24, B59, Cahier de notes, p.14. JIP, juill.–août 1868, 96–97. L’Avenir, 28 juill. 1847, juin–juill, 1857. Le Courrier de Saint-Hyacinthe, 4 sept. 1864; 21, 24, 28 nov. 1865; 27 mars 1866; 6, 9, 13 avril 1867; 25 janv., 23 avril 1868. L’Écho du cabinet de lecture paroissial, janv.–févr., 15 mars, 15 oct., 1er nov. 1864; 1er févr., 1er juill., 1er août 1865, 15 août 1866. Le Journal des Trois-Rivières, 1er mars 1867. Mélanges religieux, 16 juill., 6, 13, 20 août 1841. La Minerve, avril–mai 1837, 14 avril 1857, Le Pays, 7 mai 1867. La Revue canadienne (Montréal), 9 août 1855.
Lucien Beauregard, “La part de M. Isaac-Stanislas Désaulniers à l’introduction du thomisme au Canada français vers l’époque de la renaissance religieuse de 1840 à 1845,” Historiographie de la philosophie au Québec (1853–1970), Yvan Lamonde, édit. (Montréal, 1972), 113–30. Napoléon Caron, Histoire de la paroisse d’Yamachiche (précis historique) (Trois-Rivières, 1892). C.-P. Choquette, Histoire du séminaire de Saint-Hyacinthe depuis sa fondation jusqu’à nos jours (2v., Montréal, 1911–12), I. L.-O. David, Monsieur Isaac S. Désaulniers; prêtre, professeur de philosophie au séminaire de Saint-Hyacinthe (2e éd., Montréal, 1883). J.-A.-I. Douville, Histoire du collège-séminaire de Nicolet, 1803–1903, avec les listes complètes des directeurs, professeurs et élèves de l’institution (2v., Montréal, 1900), II, 143. [J.-S. Raymond], Éloge de messire I. S. Lesieur-Desaulniers prononcé à la distribution des prix du séminaire de St.-Hyacinthe, le 7 juillet 1868 (Saint-Hyacinthe, Qué., 1868). Émile Chartier, “Figure d’éducateur, messire Isaac-Stanislas Désaulniers (1811–1868),” RSC Trans., 3rd ser., XLII (1948), sect.i, 29–41.