Jakob Friedrich Fries

Jakob Friedrich Fries (; ; 23 August 1773 – 10 August 1843) was a German post-Kantian philosopher and mathematician.

Biography Fries studied theology at the academy of the Moravian Brethren at Niesky and philosophy at the Universities of Leipzig and Jena. After travelling, in 1806 he became professor of philosophy and elementary mathematics at the University of Heidelberg.

Though the progress of his psychological thought compelled him to abandon the positive theology of the Moravians, he retained an appreciation of its spiritual or symbolic significance. His philosophical position with regard to his contemporaries had already been made clear in his critical work Reinhold, Fichte und Schelling (1803), and in the more systematic treatises System der Philosophie als evidente Wissenschaft (1804) and Wissen, Glaube und Ahnung (1805). his views were emotional rather than rational. Hegel argued that Fries' methodology was not sufficiently scientific and that, therefore, his conclusions were illogical. Fries responded by accusing Hegel of defending the existing order and his own privileged position within it. He argued that "Hegel's metaphysical mushroom has grown not in the gardens of science but on the dunghill of servility." For Fries, Hegel's theories merely added up to a defence of the establishment and, specifically, the Prussian authorities.

Works The most important of the many works written during his Jena professorship are: Neue oder anthropologische Kritik der Vernunft (The New or Anthropological Critique of Reason, 1807) Ueber die Gefährdung des Wohlstandes und Charakters der Deutschen durch die Juden (On the Danger Posed by the Jews to German Well-Being and Character, 1816) Handbuch der praktischen Philosophie (Handbook of Practical Philosophy, 1817–1832) Handbuch der psychischen Anthropologie (Handbook of Psychical Anthropology, 1820–1821) Die mathematische Naturphilosophie (The Mathematical Philosophy of Nature, 1822) System der Metaphysik (System of Metaphysics, 1824)