Universals are referents that can be found in particular objects or concepts. For example, take the color red. A person who believes in universals would say that “redness” is a universal concept that can be found in particular objects such as fire engines, apples, and red crayons. Universals can also include abstract concepts such as “goodness.” For example, the universal of goodness can be seen in particular events such as a person saving a child from drowning or a group of men in a helicopter bringing needed food and water to victims of a natural disaster.
Debate exists as to whether universals exist apart from particular objects. Plato and the Platonic school that followed him believed that universals exist apart from any particular manifestations of that universal. Thus, if red objects ceased to exist the universal of redness would still exist. Aristotle, however, argued that universals do not exist outside of particular objects; instead, universals exist only in things.
To compare these two schools of thought consider the concept of “whiteness.” Plato would say that “whiteness” has an existence apart from any examples of whiteness on this earth. Aristotle’s view, though, is that “whiteness” does not exist apart from particular objects that are white. Thus, whiteness is connected to objects such as a white horse or a white rock. If there were no white objects, there would be no whiteness.
For Plato, universals transcend this world; for Aristotle, universals are inherently linked to objects in this world. Not every philosopher accepts the concept of universals. Some view universals as creations of the human mind to help categorize the world.