The problem of universals is one of the oldest problems in philosophy. From Plato and Aristotle to Boethus, Abelard, and the other medievals to the modern and contemporary periods philosophers have discussed whether universal words such as “man,” “dog,” “oak tree” or “water” exist in themselves, are mere labels for objects we group together for our convenience, or do not refer to things, but to objective similarities between things. Extreme realism, such as held by Plato, holds that universal terms such as “dog” refer to the Form “Dog” that exists in a spaceless, timeless world separate from the empirical world, and which is known by reason, not by sense experience. The opposite view, extreme nominalism, associated with Foucault and Derrida (although whether this is their actual position can be debated) holds that “dog” refers to what any society labels particular animals they wish to group together as “dogs.” There is no essence of dogness, no set of necessary and sufficient conditions for dogness to which the term “dog” refers. Finally, moderate realism (the position of Abelard (perhaps–I think so), St. Thomas Aquinas, and the Blessed Duns Scotus, asserts that universal terms refer to objective similarities between natural kinds of the same type, to a set of, say, necessary and sufficient conditions that make a dog a “dog.” The trend since William of Occam has been toward conceptualism, such as Occam’s notion of universals as labels that refer to similarities between entities that have some basis in extramental reality. He sounds like a moderate realist; some interpreters call him a “realistic conceptualist.” In his own day he was interpreted as a nominalist, and whatever his position may have been, philosophers after Occam gravitated toward nominalism. This trend accelerated the split between faith and reason that ended the Medieval synthesis. The end stage of this process is found in Nietzsche’s work, which supported nominalism in the sense that all meanings are culturally constructed and do not have an objective basis in extramental reality. Contemporary English Departments at many universities, especially in the United States, tend toward a radical nominalism and linguistic constructivism in which universal words refer to whatever fits a particular society’s interest. Even though I agree with the notion that meaning is flexible, since I accept the medieval four-fold model of meaning in Biblical interpretation, there remain limits to the scope of meanings that a word can have. Meaning occurs in context, and a particular context may both increase the number of possible meanings of a term, but it can also lower or eliminate the possibilities of other meanings. “I am going to the bank” makes sense if the person saying that also adds “to go fishing.” If he says, “I am going to the bank to withdraw money,” that eliminates the the other meaning of “bank” as “bank of a river.” Natural kind terms clearly refer to entities that are objectively similar. Sure, a beagle does not look like a Rottweiler, but they are both carnivores, they both bark, they can interbreed, and they have similar genetic codes and similar causal powers. There is no need to posit the existence of “Dogness” in any transcendent world independently of actual dogs. “Dogness” might exist in individual dogs in the sense that it refers to the set of necessary and jointly sufficient conditions to make a dog fall under the universal term “Dog” (or another term, such as Canis, used in another language. Thus my own sympathies are with Aristotle’s and Aquinas’ moderate realism: universal terms refer to objective similarities between things that are necessary and jointly sufficient for an entity to be the kind of thing it is. Universal terms may also hint at universal ideas or patterns in the mind of God through which He created the universe and the things in it. This view, dating back to Augustine, was picked up by the Medieval philosphers such as Aquinas, and did not fade until William of Occam denied it in the fourteenth century. Moderate realism evades the problem of arbitrariness found in postmodernism as well as the over-transcendence of Plato’s world of the Forms. I am hopeful that it will be adopted by philosophers outside the Thomist school, since as Richard Weaver pointed out in his fine book, Ideas Have Consequences, nominalism helped lead to the idea that nature, including human nature, is infinitely malleable by human ingenuity. Realism, whether ultra or moderate, helps to form a stable society in which human nature and nonhuman nature are both respected. Moderate realism avoids the problems of Plato’s doctrine of participation by placing the entity to which a universal term refers “in” the individual substance. Now substance, I believe, following Fr. Norris Clarke, is “substance-as-relation,” so that the intellectual content of the object observed would “seek” (metaphorically speaking) to communicate itself as far as possible–and the observer would strive to communicate was much as possible. Through such joining of information the mind becomes “intentionally one” with the object perceived, and thereby knows it, not exhaustively–but the actual information he receives is accurate to a degree. If this is the way communication between being and mind takes place, there is no need for transcendent Forms, but there is a need for “forms” with a small “f” to guarantee stable behavior patterns among natural kinds.