Here in one convenient volume are Volumes I, II, and III – complete and unabridged – of the acclaimed reference work that has dominated the field of philosophy for two decades. Volume I surveys the main currents in Greco-Roman thought from the pre-Socratics to Neoplatonism: e.g. Thales, Pythagoras, Heraclitus, Zeno, Socrates, Plato, and Aristotle. Medieval philosophy is the scope of Volume II, which includes the contributions of such eminent philosophers as Augustine, St. Justin Martyr, Clement, Origen, Boethius, Bonaventure, Albert the Great, Thomas Aquinas, and Duns Scotus. Volume III focuses on the philosophy of the later Middle Ages and early Renaissance through a close study of such thinkers as William of Ockham, Nicholas of Cusa, the speculative mystics, the political philosophers – e.g. Machiavelli and Thomas More – Francis Bacon, and Francis Suárez.