 The inherent problems with Plato’s original theory were recognized already by Plato himself. In his Parmenides Plato famously raised several difficulties, for which he apparently did not provide satisfactory answers. Aristotle (384–322 B.C.E.), with all due reverence to his teacher, consistently rejected Plato’s theory, and heavily criticized it throughout his own work. (Hence the famous saying, amicus Plato sed magis amica  veritas).[1]  Nevertheless, despite this explicit doctrinal conflict, Neo-Platonic philosophers, pagans (such as Plotinus ca. 204–270, and Porphyry, ca. 234–305) and Christians (such as Augustine, 354–430, and Boethius, ca. 480–524) alike, observed a basic concordance between Plato’s and Aristotle’s approach, crediting Aristotle with an explanation of how the human mind acquires its universal concepts of particular things from experience, and Plato with providing an explanation of how the universal features of particular things are established by being modeled after their universal  archetypes.[2]  In any case, it was this general attitude toward the problem in late antiquity that set the stage for the ever more sophisticated medieval  discussions.[3]  In these discussions, the concepts of the human mind, therefore, were regarded as posterior to the particular things represented by these concepts, and hence they were referred to as universalia post rem (‘universals after the thing’). The universal features of singular things, inherent in these things themselves, were referred to as universalia in re (‘universals in the thing’), answering the universal exemplars in the divine mind, the universalia ante rem (‘universals before the  thing’).[4]  All these, universal concepts, universal features of singular things, and their exemplars, are expressed and signified by means of some obviously universal signs, the universal (or common) terms of human languages. For example, the term ‘man’, in English is a universal term, because it is truly predicable of all men in one and the same sense, as opposed to the singular term ‘Socrates’, which in the same sense, i.e., when not used equivocally, is only predicable of one man (hence the need to add an ordinal number to the names of kings and popes of the same name).