Medieval philosophy engaged with many of the same metaphysical, epistemological, and ethical questions as ancient philosophy. However, medieval thinkers approached these questions within the framework of the monotheistic religions of Judaism, Christianity, and Islam. As a result, certain themes and problems took on a heightened importance during this era as philosophers tried to reconcile reason with faith. Three issues that generated significant debate across the different medieval traditions were the eternity of the world, divine omniscience and human freedom, and the nature of the soul and immortality.
The Eternity of the World
The question of whether the world is eternal or created was a major point of contention between medieval philosophy and religious doctrine. Aristotle argued that the world is eternal based on the metaphysical principle that everything that comes into being must have a preceding cause. Since there cannot be an infinite regress of causes, there must be an eternal substratum that caused the world. This eternal cosmic order precludes any notion of creation ex nihilo.
Jewish, Christian, and Islamic theology, in contrast, maintained that God created the world at a finite point in the past. The doctrine of creation was seen as essential for establishing God’s omnipotence and sovereignty. An eternal world would seem to impinge on God’s absolute power.
One of the first to challenge Aristotle on this issue was the Christian philosopher John Philoponus (c. 490–c. 570). Philoponus argued that an eternally existing world would imply an actual infinity, which Aristotle himself rejected as absurd. An infinite temporal regress of days, for example, is merely potential but not actual. Therefore, the world must have had a temporal beginning.
Arabic and Jewish philosophers in the Aristotelian tradition, however, insisted that creation did not require a temporal beginning. Al-Farabi, Avicenna, Averroes and others held that God eternally causes the world through a hierarchical emanation of intellects and souls. Maimonides provided extensive arguments against the Aristotelian position, maintaining that it contradicts core Jewish doctrines. But he did not think Aristotle actually demonstrated the eternity of the world, and offered alternative scientific explanations for the origin of the universe.
Among Latin Christian thinkers, Thomas Aquinas argued that based on reason alone the world could be either eternal or created. Faith tells us that the world did in fact have a beginning, but there is no philosophical contradiction in positing an eternal created universe. Aquinas sharply distinguished this from the unorthodox view that the world is uncreated or exists necessarily apart from God. Other scholastics rejected Aquinas’s reconciliatory approach and argued vigorously that temporal creation can be philosophically proven.
Divine Omniscience and Human Freedom
If God fully knows the future, how can humans have free will? This paradox deeply troubled medieval philosophers. Complete divine foreknowledge would seem to preclude any possibility of contingent choices or alternative possibilities.
An early discussion is found in Boethius’s Consolation of Philosophy (c. 524). Boethius argues that God’s timeless vantage point allows him to see all temporal events at once. While future contingents remain uncertain to limited human knowers, they are eternally present to God’s timeless knowledge.
Later scholastic thinkers like Aquinas largely followed Boethius’s solution, while adding technical precision. Aquinas held that God’s knowledge does not depend on things but rather causes them to be. The divine mind does not passively register future events, but actively wills and produces them.
In the late 13th century, John Duns Scotus revolutionized the debate by rejecting this Thomistic stance. Scotus argued that divine foreknowledge is only compatible with free will if God himself wills contingently. Scotus analyzed modal concepts like possibility and necessity independently from temporal conditions, allowing him to conceive of God freely choosing amongst possibilities.
Other medieval thinkers pursued more unorthodox routes to preserve human freedom. The Jewish philosopher Gersonides restricted God’s knowledge to universals and argued that the details of human life are determined indirectly by the stars. Humans can overcome astral fate through intellectual self-mastery. So although physically predetermined, humans remain free in their rational capacities.
In contrast, Gersonides’s contemporary Hasdai Crescas affirmed strict determinism, considering free will and moral responsibility compatible with causal necessity. According to Crescas, an agent acts freely not by uncaused spontaneity but by following an internal causal chain of rational deliberation. Determinism does not render human striving futile but is the precondition for achieving our goals.
The Soul and Immortality
Questions about the nature of the human soul and its survival after bodily death were pressing issues for medieval philosophers. Aristotle conceived of the soul as the animating form of the body—the vital power that enables living functions. The intellect alone is immaterial, but it is unclear if Aristotle viewed individual intellects as immortal.
An opposite perspective came from Platonism, which saw the soul as an immaterial substance distinct from the body and capable of existing separately. Augustine synthesized Neoplatonism with Christian belief in the individual soul’s judgment and eternal salvation or damnation.
Islamic philosophers expressed divergent interpretations of Aristotle. Avicenna argued that each person has an individual intellect that survives death. He reasoned that intellect, since it grasps universal concepts, must be immaterial. Averroes, however, asserted that Aristotle posited a single universal material intellect shared by all humans. Individual immortality for Averroes meant union with this universal mind.
Aquinas adamantly rejected Averroes’s view as contradictory to Christian doctrine. But he also denied Augustine’s radical Platonic dualism. Against Avicenna, Aquinas claimed the human intellect cannot function without the body, since abstract cognition requires accompanying mental images provided by the senses. The intellect’s immateriality, for Aquinas, simply means it transcends matter in its operation. The separated soul remains uniquely identifiable with the body so that both can be reunited at resurrection.
In early modernity, Pietro Pomponazzi revived the Averroist interpretation of Aristotle as the most rationally compelling view, though one forbidden by faith. This provoked the ire of Church authorities who saw it as undermining Christian truths. Pomponazzi’s goal was to assert philosophy’s autonomy, not its superiority over theology. His polemical stance illustrates the tension between reason and revelation running throughout medieval debates.
The core problems of medieval philosophy remain relevant in enriched form today. Questions about the origins of the universe, human freedom, consciousness, and personal identity continue to animate contemporary philosophical discourse. By appreciating medieval reflections on these ideas, we gain insight into our own thinking and discover subtle dimensions that endure across intellectual epochs.
Summary
The medieval era comprised a rich diversity of philosophical traditions, despite prevailing misconceptions about it as an age of religious orthodoxy and intellectual stagnation. The dynamic interplay between monotheistic faiths and Greek reason yielded sophisticated philosophical systems and noveldevelopments in logic, metaphysics, and ethics. Key themes included reconciling creation and eternity, upholding providence along with human freedom, and probing the mind-body relationship. Medieval debates featured sophisticated analyses of concepts like possibility, time, and personal identity, with extensive commentaries analyzing these notions from every angle. Later philosophy evolved by appropriating, extending, or reacting against uniquely medieval paradigms and problems. Though differing in premises and conclusions, medieval thinkers practiced philosophy as a tradition of rational discourse and systematic inquiry. Their enduring contributions remind us that human thought retains continuity even across wide spans of time, place, and culture.
