Medieval philosophy designates the philosophical speculation that occurred in western Europe during the Middle Ages—i.e., from the fall of the Roman Empire in the 4th and 5th centuries ad to the Renaissance of the 15th century. Philosophy of the medieval period was closely connected to Christian thought, particularly theology, and the chief philosophers of the period were churchmen. Philosophers who strayed from this close relation were chided by their superiors. Greek philosophy ceased to be creative after Plotinus in the 3rd century ad. A century later, Christian thinkers such as