Clicking on the authors' names (or book titles where there is no author) will take you either to their Google directory, if they have one, or to Google search results. Unless noted otherwise, all works listed here are complete editions, and not selections or abridgements. I hate abridgements and will always try to read works in their entirety.
Hume: A Dialogue; Dialogues Concerning Natural Religion; An Enquiry Concerning Human Understanding; An Enquiry Concerning the Principles of Morals; Essays, Moral, Political, and Literary; My Own Life; The Natural History of Religion; A Treatise on Human Nature.
James: Human Immortality; Pragmatism; The Will to Believe and Other Essays.
Kant: The Groundwork of the Metaphysics of Morals.
Leibniz: Discourse on Metaphysics; Monadology; Nature Itself; New Essays on Human Understanding; New System of Nature; Principles of Nature and Grace; Reflections on True Metaphysics; Specimen Dynamicum; Theodicy.
Spinoza: Ethics; Treatise on the Improvement of the Intellect; Metaphysical Thoughts; A Political Treatise; Principles of Cartesian Philosophy; Theologico-Political Treatise.