Crusius, Christian August

Crusius, Christian August (1715-1775): German, Philosopher.

Christian August Crusius was the most important opponent of Wolffian rationalism to work within the Thomasian-Pietistic tradition. Born in Leuna, Saxony, Crusius studied philosophy in Leipzig under the direction of Adolf Friedrich Hoffman, whose views he developed systematically in his dissertations (1739-45). After he was appointed professor of philosophy in 1744, Crusius authored a series of works that contributed to the swift decline of rationalism in Europe. His Advice for a Rational Life (1744) argues, contrary to what he considers Wolff’s concealed spiritual mechanism that freedom consists in the power to act according to one’s idea of the good, for the sake of either prudence or virtue. And, in the Entwurf der nothwendigen Vernunftwahrheiten (1745), Crusius rejects Wolff’s attempt to model philosophy after mathematics and criticizes rationalists’ unfounded inferences from how we think of things to how things are in themselves. Crusius gradually lost interest in philosophy, however, and was appointed professor of theology in 1751. He later founded the Biblicoprophetic theological school, where his teachings partially diverged from Pietism, and became canonical at the Meissen Theological Seminary before his death in 1775.

In addition to the immediate influence Crusius had on such anti-Wolffian academics such as A. F. Reinhard and Gellert, Christian Fürchtegott, he profoundly impacted the young Kant, Immanuel by anticipating his disagreements with the Leibnizian/Wolffian philosophy — specifically, his theories of the will and of the pure concepts of the understanding.

Further Reading:

Lewis White Beck, Early German Philosophy: Kant and His Predecessors, 1969.

Matthew Altman