Discourse on Metaphysics and The Monadology
G. W. Leibniz
A Treatise of Human Nature
David Hume
Discourse on Method and Meditations
René Descartes
Discourses (Books 1 and 2)
Epictetus
Discourses (Books 3 and 4)
Epictetus
Human, All-Too-Human
Friedrich Nietzsche
Plato's Theory of Knowledge
Plato & Francis M. Cornford
The Phenomenology of Mind
G. W. F. Hegel & J. B. Baillie
A Treatise Concerning the Principles of Human Knowledge
George Berkeley
Laws
Plato