1. Plato. Meno. 1997. Translated by Grube, G.M.A. In Plato: Complete Works, ed. J.M. Cooper. Indianapolis: Hackett.
2. Plato. Phaedrus. 1997. Translated by Nehamas, Alexander and Woodruff, Paul. In Plato: Complete Works, ed. J.M. Cooper. Indianapolis: Hackett.
3. Plato. Republic. 1997. Translated by Grube, G.M.A. Revised by Reeve, C.D.C. In Plato: Complete Works, ed. J.M. Cooper. Indianapolis: Hackett.
4. Chalmers, A.F. 1976. What is this Thing Called Science? Indianapolis: Hackett.
5. Foley, R. 2008. Plato’s Undividable Line: Contradiction and Method in Republic VI. Journal of the History of Philosophy 46 (1): 1–23.