Theism—the doctrine that there is only one God, who has a personal and direct relation to the universe—is the point of departure for these twelve lectures delivered in 1870 and 1890, revised for publication in 1893. Included here are off-the-beaten-path arguments about “The Evolution of Theism,” “The Metaphysic of Physics,” “Causality,” “The Consciousness of the Infinite,” and more.