Aristotle. “Nicomachean Ethics.” The Internet Classics Archive | Nicomachean Ethics by Aristotle, n.d.

Descartes, René. “Descartes’ Meditations.” Translated by John Veitch. Descartes’ Meditations, n.d.

Epicurus. “Principal Doctrines.” Translated by Hicks, Robert Drew. The Internet Classics Archive | Principal Doctrines by Epicurus, n.d.

Hobbes, Thomas. “Leviathan.” Leviathan, by Thomas Hobbes, October 11, 2009.

Hume, David. “An Enquiry Concerning Human Understanding.” The Project Gutenberg eBook of An Enquiry Concerning Human Understanding, by David Hume., n.d.

Kant, Immanuel. “Fundamental Principles of the Metaphysic of Morals.” Translated by Thomas Kingsmill Abbott. Fundamental Principles of the Metaphysic of Morals by Immanuel Kant – Project Gutenberg, n.d.

———. “Prolegomena to Any Future Metaphysics.” Translated by Paul Carus. Full Text of “Kant’s Prolegomena to Any Future Metaphysics”, n.d.

Locke, John. “An Essay Concerning Human Understanding.” An Essay Concering Human Understanding, n.d.

Machiavelli, Nicolo. “The Prince.” Translated by W. K. Marriott. The Prince, by Nicolo Machiavelli, n.d.

Marcus Aurelius. “The Internet Classics Archive | The Meditations by Marcus Aurelius.” Translated by Long, George, n.d.

Marx, Karl, and Friedrich Engels. “Manifesto of the Communist Party.” Manifesto of the Communist Party, 2000.

Mill, John Stuart. “Utilitarianism.” Utilitarianism by John Stuart Mill, n.d.

Nietzsche, Friedrich. “Beyond Good and Evil.” Translated by Helen Zimmern. Beyond Good and Evil, by Friedrich Nietzsche, n.d.

Plato. “Phaedo.” Translated by Benjamin Jowett. The Internet Classics Archive | Phaedo by Plato, n.d.

———. “The Apology of Socrates.” Translated by Jowett, Benjamin. The Apology of Socrates. Plato. 1909-14. The Apology, Phædo and Crito. The Harvard Classics, 2001.

———. “The Republic.” Translated by Benjamin Jowett. The Internet Classics Archive | The Republic by Plato, n.d.

Russell, Bertrand. “The Reading Selection from Problems of Philosophy.” Reading for Philosophical Inquiry: A Brief Introduction to Philosophical Thinking Ver. 0.21; An Open Source Reader, n.d.

Sartre, Jean Paul. “L’existentialisme Est Un Humanisme.” Translated by Adam Norman and Google, n.d.