A general term for those philosophers influenced by the medieval rediscovery of classic texts, Scholasticism is broadly characterized by an interest in logic and disputation and is motivated to resolve the metaphysical disagreements between Aristotle and Plato, especially on the subject of universals. These two topics were closely related. Peter Abelard (1079–1144), for instance, argued that universality is a feature of our language, not a metaphysical distinction between types of entity. He subsequently drew several important distinctions between the signification of an expression—what it names—and the ideas of the speaker.
Abelard is also credited with developing an early form of propositional logic. William of Ockham (c. 1285–1347) similarly argued that only particulars exist and that universality is a property pertaining to names. From this, he concluded that the causal properties of objects must operate in and of themselves. That is, no sine qua non causation operates behind the scenes, and not even God could make (for example) the property of heat to cause things to cool. The conflict between Plato and Aristotle was therefore intellectually liberating, and early examples of an experimental approach, such as in the work of Roger Bacon (c. 1214–1293), can also be found in Scholasticism.
