Augustine's De Libero Arbitrio (On Free Choice of the Will), composed in stages between 388 and 395 CE, is the first sustained philosophical treatment of free will in the Western tradition. Written as a Socratic dialogue between Augustine and his friend Evodius, the work uses the literary form of rational inquiry to ask a question whose urgency had been sharpened by Augustine's years in the Manichaean sect: if God is good, why is there evil? The question is as old as Job; Augustine's answer established the terms of the debate for all subsequent Western philosophy.
The Thinker and His Work
Augustine began the work while still a catechumen in Rome, shortly after his conversion from Manichaeism in 386. The Manichaean problem - which attributed evil to a second, evil principle co-equal with God - had been Augustine's intellectual home for nearly a decade, and De Libero Arbitrio is in part a systematic refutation of that dualism through philosophical argument and biblical exegesis. The three books of the dialogue move from the problem of evil, to the existence of God, to the compatibility of foreknowledge and free will.
Biblical Texts Engaged
Genesis 3 is the narrative engine of the work. Augustine reads the fall of Adam and Eve not as a mythological event imposed from outside but as the paradigmatic philosophical analysis of how freedom goes wrong: the creature, given genuine liberty to choose between good and evil, turns away from the highest Good (God) toward a lesser good (the fruit) in an act of pride. This turning (aversio) is the root of all evil - not a positive substance but a deficiency, a turning of the will from being toward non-being.
Romans 7:15-25 - Paul's account of the divided will ('I do not do what I want, but I do the very thing I hate') - provides the phenomenological description that Augustine needs. He reads Paul not as describing unregenerate humanity alone but as analyzing the structure of fallen willing as such: the will that chooses evil is not acting freely but is enslaved to its own disorder. This creates the paradox at the heart of the free will debate: free choice produces bondage.
Romans 5:12 ('sin came into the world through one man') grounds Augustine's later development of original sin, which he will flesh out against the Pelagians - but already in De Libero Arbitrio the seeds of this doctrine are present in the analysis of inherited tendency toward disordered love.
Core Argument
Augustine's argument has three phases. First, evil is not a substance created by God but a defect of the will: when the will turns away from the eternal and immutable Good toward mutable, created goods, it disorders itself. God created the will free - genuinely capable of choosing otherwise - and this freedom is the necessary condition for moral goodness. A being that cannot choose evil cannot genuinely choose good.
Second, God's foreknowledge of free choices does not undermine their freedom. Augustine draws the analogy of a human observer who watches a person make a choice: the observer's knowledge of the choice does not cause it. God's eternal knowledge of all temporal events is analogous - it is the knowledge of a simultaneous eternal present, not deterministic causation.
Third, the will's bondage after the fall raises the question of grace, which Augustine addresses more fully in his anti-Pelagian writings but which is already implicit here: if the will is disordered by sin, it cannot restore itself by its own power. This is not a denial of free will but a description of freedom's pathology.
Intellectual Context
Augustine was working within - and transforming - the Platonic tradition. Plotinus had argued that evil is non-being, the failure of the material to participate in the Good; Augustine adapts this but gives it a volitional character: evil is the will's failure, not matter's. His dialogue form echoes the Socratic dialogues, and his argument that the existence of truth (including the truths of mathematics) points toward an eternal, immutable Truth (God) is a version of the Platonic theory of the Forms re-narrated through Exodus 3:14 ('I AM WHO I AM').
Reception and Critique
Perlagius and his followers argued that Augustine's account of sin's bondage destroyed moral responsibility and made God the author of evil. Augustine's responses - On the Spirit and the Letter, On Nature and Grace, On the Predestination of the Saints - refined and hardened the Augustinian position into what became the doctrine of predestination. Erasmus, in On Free Will (1524), returned to the Augustinian dialogue format to argue for a more optimistic anthropology, drawing on the same Pauline and wisdom texts. Luther's response, On the Bondage of the Will (1525), declared De Libero Arbitrio the most important statement of the problem.
In the twentieth century, Alvin Plantinga's 'free will defense' against the logical problem of evil (in God, Freedom, and Evil, 1974) is the direct philosophical descendant of Augustine's argument: God cannot create free creatures and also ensure they always choose good, because that would be a contradiction. The argument that has occupied analytic philosophy of religion for fifty years was first assembled through Augustine's reading of Genesis 3 and Romans 7.
Legacy
De Libero Arbitrio established the vocabulary of the free will debate: liberum arbitrium (free choice), voluntas (will), gratia (grace), praescientia (foreknowledge). It defined the problem - how to reconcile human freedom, divine goodness, and the reality of evil - in terms that have governed Western philosophy and theology ever since. Every major position in the debate, from Calvinist determinism to Arminian libertarianism to contemporary compatibilism, is defined partly by its relationship to Augustine's framework.
Key Passages
'The cause of evil is the free decision of the will' (Book I.16, trans. Williams)
'God is the highest good, and it is better to have free choice of the will, even if it can be used badly, than not to have it at all.' (Book II.18)
Contemporary Relevance
The free will debate is more active in contemporary philosophy than at any point since the Reformation, driven by advances in neuroscience that appear to challenge the existence of libertarian free will. Augustine's framework remains relevant because he was the first to clearly distinguish the philosophical question (can the will be genuinely free and yet disordered?) from the theological question (can grace restore freedom without abolishing it?). His analysis of akrasia - the will's acting against its own best judgment - anticipates contemporary philosophical psychology's interest in weakness of will, addiction, and the fragmentation of agency.