PESCH, TILLMANN. – Jesuit, brother of the preceding, philosopher, born in Cologne on 1 February 1836, died at Valkenburg on 18 October 1899.
He entered the Society of Jesus (1852) and was ordained a priest (1866); he was professor of philosophy to his fellow religious at Maria Laach (1867–69). From that time he distinguished himself by his love and esteem for Aristotelian-scholastic philosophy, which in those days was already regarded as outdated in both content and method; and he conceived the plan of restoring Christian philosophy in Germany through an effective defence and exposition of medieval philosophy, enriched and adapted to the achievements of modern science. Indeed, he played a major part in the renewal of Catholic philosophy, initiated by Fr. KLEUTGEN, JOSEPH (v.), contributing, even before the encyclical Aeterni Patris (v.), to the return to the fundamental theories of Scholasticism, in accordance with the will of Leo XIII. After a brief interval devoted to the priestly ministry (1870–1872), he went to Tervueren (Belgium) to join the editorial staff of the periodical Stimmen aus Maria Laach, and there began the parallel publication of the Ergänzungshefte. From 1876 to 1884, while continuing his work as a writer, he again taught philosophy at Blüenbek, Exaeten, and Valkenburg.
In addition to the numerous articles in Stimmen defending medieval philosophy, he composed for the Ergänzungshefte series, against Kant’s theories: Die moderne Wissenschaft betrachtet in ihrer Grundfeste (Freiburg im Breisgau 1876); Haltlosigkeit der modernen Wissenschaft, eine Kritik der Kant'schen Vernunftsbricht (ibid. 1879); Das Weltphänomen. Eine erkenntnistheoretische Studie (ibid. 1881). Meanwhile he developed the plan for a complete course in philosophy, entitled Philosophia lacensis, and opened the series with Institutiones philosophiae naturalis (Cosmogony [2 vols., ibid. 1880; 2nd ed., ibid. 1887]), which earned him appointment as a member of the Academy of St Thomas of Bologna. These were followed by: Institutiones logicales (3 vols., ibid. 1888–90; new edition edited by Fr. C. Frick, Institutiones logicae et ontologiae, 2 vols., ibid. 1914–19); Institutiones psychologiae (3 vols., ibid. 1896–98). Another notable publication is Die grossen Welträtsel. Philosophie der Natur allen Naturfreunden dargeboten (2 vols., ibid. 1883–84; 3rd ed., ibid. 1907), in which, with the aid of all the sciences, he refuted the manifold aberrations of materialism, atheism, and monism, then very widespread. Against Lutheranism, on the occasion of the centenary celebrations of Luther in 1883, he launched a lively apologetic work under the pseudonym “Gottlieb”: Briefe aus Hamburg (2 vols., ibid. 1883–89; 5th ed., ibid. 1905), a defence of the Church against the assertions of seven well-known opponents of the divinity of Jesus Christ; this later became vol. I of the work Christ oder Antichrist, to which he added, as vol. II, Der Krach von Wittenberg (ibid. 1890; 2nd ed. 1894). In the ascetical field he wrote Das religiöse Leben (ibid. 1878; 23rd ed., ibid. 1922), a booklet of prayers and advice for educated men, and Christliche Lebensphilosophie (ibid. 1895, 22nd ed. 1923). He also founded the apologetic collection Flugschriften zur Lehr und Wehr, which was distributed in more than a million copies.