“ The most important works of this period of his life are Entwurf der nothwendigen Vernunftwahrheiten (1745) , and Weg zur Gewissheit und Zuverlässigkeit der menschlichen Erkenntniss (1747) . Though diffusely written, and neither brilliant nor profound, Crusius’ philosophical books had a great but short-lived popularity. His criticism of Wolff, which is generally based on sound sense, had much influence upon Kant at the time when his system was forming; and his ethical doctrines are mentioned with respect in the Kritik of Practical Reason. Crusius’s later life was devoted to theology. ”