Epistemology

Leibniz's New Essays Concerning the Human Understanding: A Critical Exposition

The Opinions of a Philosopher

Manhood of Humanity

The Philosophy and Theology of Averroes

Creation or Evolution? A Philosophical Inquiry

The Jumble Book: A Jumble of Good Things

Some Turns of Thought in Modern Philosophy

Essays in Radical Empiricism

Modern Skepticism: A Journey Through the Land of Doubt and Back Again

Our Intellectual Strength and Weakness

Aphorisms and Reflections from the Works of T. H. Huxley

On the Improvement of the Understanding

Civilization

Ingersollia

Phaedrus

The Philosophy of Evolution

The Advancement of Learning

Flowers of Freethought (Second Series)

The Philosophy of Mystery

On Sense and the Sensible