"Medieval philosophy is conventionally construed as the philosophy of Western Europe between the decline of classical pagan culture and the Renaissance. Such a broad topic cannot be covered in detail in a single article, and fortunately there is no need to do so, since other articles in this Encyclopedia treat individual medieval philosophers and topics. The present article will confine itself to articulating some of the overall contours of medieval philosophy."
"St. Augustine is a fourth century philosopher whose groundbreaking philosophy infused Christian doctrine with Neoplatonism. He is famous for being an inimitable Catholic theologian and for his agnostic contributions to Western philosophy. He argues that skeptics have no basis for claiming to know that there is no knowledge. In a proof for existence similar to one later made famous by René Descartes, Augustine says, '[Even] If I am mistaken, I am.' He is the first Western philosopher to promote what has come to be called 'the argument by analogy' against solipsism: there are bodies external to mine that behave as I behave and that appear to be nourished as mine is nourished; so, by analogy, I am justified in believing that these bodies have a similar mental life to mine. Augustine believes reason to be a uniquely human cognitive capacity that comprehends deductive truths and logical necessity. Additionally, Augustine adopts a subjective view of time and says that time is nothing in reality but exists only in the human mind’s apprehension of reality. He believes that time is not infinite because God 'created' it."
Pseudo-Dionysius the Areopagite
"Dionysius is the author of three long treatises (The Divine Names, The Celestial Hierarchy, and The Ecclesiastical Hierarchy) one short treatise (The Mystical Theology) and ten letters expounding various aspects of Christian Philosophy from a mystical and Neoplatonic perspective. Presenting himself as Dionysius the Areopagite, the disciple of Paul mentioned in Acts 17:34, his writings had the status of apostolic authority until the 19th century when studies had shown the writings denoted a marked influence from the Athenian Neoplatonic school of Proclus and thus were probably written ca. 500. Although the attribution of authorship has proven to be a falsification, the unknown author (hereafter referred to as Ps-Dionysius) has not lost his credibility as an articulate Athenian Neoplatonist expressing an authentic Christian mystical tradition. Indeed with eloquent poetic language and strong exposition of ideas, the Dionysian corpus ranks among the classics of western spirituality."
"William of Ockham, also known as William Ockham and William of Occam, was a fourteenth-century English philosopher. Historically, Ockham has been cast as the outstanding opponent of Thomas Aquinas (1224-1274): Aquinas perfected the great “medieval synthesis” of faith and reason and was canonized by the Catholic Church; Ockham destroyed the synthesis and was condemned by the Catholic Church. Although it is true that Aquinas and Ockham disagreed on most issues, Aquinas had many other critics, and Ockham did not criticize Aquinas any more than he did others. It is fair enough, however, to say that Ockham was a major force of change at the end of the Middle Ages. He was a courageous man with an uncommonly sharp mind."
"Within his large body of work, Thomas treats most of the major sub-disciplines of philosophy, including logic, philosophy of nature, metaphysics, epistemology, philosophical psychology, philosophy of mind, philosophical theology, the philosophy of language, ethics, and political philosophy. As far as his philosophy is concerned, Thomas is perhaps most famous for his so-called five ways of attempting to demonstrate the existence of God. These five short arguments constitute only an introduction to a rigorous project in natural theology—theology that is properly philosophical and so does not make use of appeals to religious authority—that runs through thousands of tightly argued pages. Thomas also offers one of the earliest systematic discussions of the nature and kinds of law, including a famous treatment of natural law. Despite his interest in law, Thomas’ writings on ethical theory are actually virtue-centered and include extended discussions of the relevance of happiness, pleasure, the passions, habit, and the faculty of will for the moral life, as well as detailed treatments of each one of the theological, intellectual, and cardinal virtues. Arguably, Thomas’ most influential contribution to theology and philosophy, however, is his model for the correct relationship between these two disciplines, a model which has it that neither theology nor philosophy is reduced one to the other, where each of these two disciplines is allowed its own proper scope, and each discipline is allowed to perfect the other, if not in content, then at least by inspiring those who practice that discipline to reach ever new intellectual heights."
