* David Hume's empiricist theory of knowledge.

* Hume's metaphysical skepticism (or "why Hume's theory of knowledge makes most claims about reality unknowable.").

* Immanuel Kant's theory of knowledge.

* how Kant's epistemology restores many of the claims Hume said we couldn't know.

* why Kant is still a skeptic concerning claims about how things really are, independent of experience.

* how Georg Wilhelm Friedrich Hegel turns Kant 's skepticism into the all-embracing metaphysics of absolute idealism.

* the continental reactions to Hegel's "System" from Soren Kierkegaard, Arthur Schopenhauer, Sigmund Freud, and Friedrich Nietzsche.