Property (philosophy)

In logic and philosophy (especially metaphysics), a property is a characteristic of an object; a red object is said to have the property of redness. The property may be considered a form of object in its own right, able to possess other properties. A property, however, differs from individual objects in that it may be instantiated, and often in more than one object. It differs from the logical/mathematical concept of class by not having any concept of extensionality, and from the philosophical concept of class in that a property is considered to be distinct from the objects which possess it. Understanding how different individual entities (or particulars) can in some sense have some of the same properties is the basis of the problem of universals. A property is any member of a class of entities that are capable of being attributed to objects. Terms similar to property include predicable, attribute, quality, feature, characteristic, type, exemplifiable, predicate, and intensional entity. Generally speaking, an object is said to exemplify, instantiate, bear, have or possess a property if the property can be truly predicated of the object. The collection of objects that possess a property is called the extension of the property. Properties are said to characterize or inhere in objects that possess them. Followers of Alexius Meinong assert the existence of two kinds of predication: existent objects exemplify properties, while nonexistent objects are said to exemplify, satisfy, immanently contain or be consubstantiated by properties that are actually possessed and are said to encode, be determined by, be consociated with or be constituted by properties that are merely ascribed to objects. For example, since Pegasus is merely mythical, Pegasus encodes the property of being a horse, but Pegasus exemplifies the property of being a character of Greek mythology as well. Edward Jonathan Lowe even treated instantiation, characterization and exemplification as three separate kinds of predication.