October 18

Christian August Crusius (1715–1775) was a professor at the University of Leipzig where he championed a moral philosophy rooted in common sense. He attacked the Leibniz–Wolff school’s rationalist determinism and defended human freedom. His major works, such as Entwurf der nothwendigen Vernunftwahrheiten, laid groundwork for critiques of speculative metaphysics. As a theologian, he emphasized sincerity in Christian faith and shaped Lutheran doctrine. His writings influenced later philosophers, most notably Immanuel Kant, by insisting on the limits of pure reason and the importance of practical reason.

Born in Germany, Leo Strauss taught at universities in Europe before emigrating to the United States in 1937. He became a professor at the New School and later at the University of Chicago, where he developed his distinctive approach to political philosophy. Strauss championed the careful reading of ancient thinkers like Plato and Aristotle, arguing that hidden meanings could unlock enduring truths. His ideas on esoteric writing and natural right influenced a generation of scholars and policymakers. Strauss's work remains central to debates in philosophy, politics, and education.