He wrote more than 5 million words, so we have plenty of verified texts from him. He discovered philosophy in 373. Eventually, he converted to Christianity in 387. His most famous book is the "Confessions," created between 397 and 401. It is a first person account of his intellectual and spiritual journey. He writes about his "conversion;" it is a confession in every sense of the term. His style is influenced by Cicero. Augustine does not like Aristotle very much; he is mostly influenced by Platonic thought. 

Augustine looks for ways to unite Christian revelation and Platonic metaphysics. One may speak of Augustine’s Christianization of Greek metaphysics, but he also develops a metaphysical reading of Christianity

Augustine begins his Confessions with the human heart’s inquietude, the "inquietum cor nostrum" (Confessions, I, 1.) Existence alone is a question in itself, and our existence’s perpetual restlessness stems, as Augustine explains in a Plotinian manner, from its multifarious dispersion (in multa defluximus) which he associates with corporeal, or sensual, temptations. His Confessions are the tale of the heart’s conversion and retreat from bodily temptations, curiosity, and ambition, toward the One in which the soul can finally find solace. God is thus “rest” itself, as he says in the last lines of the Confessions

"Cor curvatum in se ipsum:" this is what Augustine calls the condition of human sin: the heart is turned into itself. ("in sich selbst verkrümmtes Herz.")  Augustine says that when humans, in their finitude, seek in vain to be their own principle, they turn away from the divine stabilitas (II, 10, 28) and enter a state of extreme poverty ("regio egestatis"). Augustine was close to Manichaeism for a while, but later he rejected the idea that God has in himself a duality of principles. Evil comes not from a fundamental metaphysical principle, but from the closure of the human heart. Platonism, with its understanding of transcendence, is more suitable to explain this Christian view of human existence. 

Augustine’s reflections are very important for metaphysics since they are a meditation on our temporal condition.

Christians believe that the Word was "made flesh" in Jesus Christ.  But the most important idea for Augustine is the call to transcend the sensible. The soul is distracted in this sensible world. It is agitated, restless, it longs for the “intelligible world,” which is its real home. In the masterpiece of his later period, Augustine calls the soul’s intelligible home The City of God, which is also an idea inspired by Neoplatonism.

More than anyone else, Augustine contributed to the Christian appropriation of the Platonic horizon of thought and the idea of an intelligible world which is more essential than our own. Augustine created the foundations of medieval metaphysics by unifying the supreme wisdom sought by the Greeks, the science of the first principles of Being as Being, and the revealed wisdom of Holy Scripture.

In the following, I will discuss two key philosophical issues:  The interplay of faith and reason, and the problem of evil.  

The Interplay of Faith and Reason

For Augustine, like Plato and Plotin, the highest truth consists in grasping the idea of the Good. Augustine interprets the idea of the Good as the existence of God. The ancient Greeks held reason to be eternal and belief to be changeable, whereas early Christians held faith to be eternal and knowledge to be changeable. 

Consider the Platonic idea of the Good: It is universally and eternally true and, while experience can mislead us because it gives us only the shadowy representations of forms, human reason permits us to know the Good to some degree. Since Augustine was a Neoplatonist, we would assume that he would privilege the side of reason over faith. He also rejects Manichaeism, the idea that good and evil co-exist as dualistic principles, based on philosophical arguments. Nevertheless, Augustine rarely relies on reason alone.  In fact, he argues in the Confessions that reason is the greatest hindrance to the full acceptance of faith.   

For Augustine, the foundational premise for the idea of the Good is Faith: “Unless you believe, you shall not understand.”  Reason is the tool which permits understanding of the truth in which we believe. Reason extends and deepens faith. And reason can initiate faith: for the disbeliever may use reason alone to start moving toward God. Thus, reason operates as a preparation for faith.

This interplay of faith and reason is not just an intellectual project, because we resist and refuse to understand, for reasons that are hard to explain. This difficulty operates also in Plato's philosophy and leads to the tragedy of Socrates' death. In Plato, the use of reason is described as a difficult struggle: Socrates is the annoying questioner who always challenges the common understanding or the un-reflected acceptance of an idea. He frequently exposes the ignorance in his interlocutors who often terminate the dialog because they are cornered. Socrates was put on trial and sentenced to death because many Athenians became angry with his pursuit of wisdom that exposed their ignorance. At his trial, Socrates says that “the unexamined life is not worth living.” So what is missing in the pursuit of a good life?

Augustine faces the same problem: “… mind can be present in man, and yet not have control.”  In the Confessions, we see his profound struggle with coming to know the truth. It is very easy for the mind to get seduced and become disordered.  People pursue temporal goals as opposed to the eternal truth; their blindness leads to despair and failure on many levels. Augustine also advises people to cultivate the four cardinal virtues (prudence, fortitude, temperance, and justice) and to avoid evil thoughts and actions. The struggle for truth is existential or religious, and it is most important for people to work this out in their own lives. 

There is an interesting undercurrent to this struggle which must be conducted through both reason and faith: We struggle against our own desires by the strength of our desire. Augustine describes what happens when lust dominates the mind:

"… the reign of lust rages tyrannically and distracts the life and whole spirit of man with many conflicting storms of terror, desire, anxiety, empty and false happiness, torture because of the loss of something that he used to love, eagerness to possess what he does not have, grievances for injuries received, and fires of vengeance" (Augustine, On the Free Choice of the Will, Bk.I). 

These “storms” caused by the reign of lust are terror, desire, and anxiety. They distract us from “enlightenment,” and from understanding the truth through a reflection of our faith in God.  The reign of lust produces the same emotional and spiritual disorder as the pursuit of knowledge itself, which can also become a solipsistic and greedy enterprise. 

Could Augustine attain understanding, attain faith, without knowing the struggles of lust?  Do we not need to see the symmetry between desiring good and ill? Socrates claimed that his wisdom was his acknowledgement of his own ignorance; only if one recognizes one’s ignorance can one know what knowledge to look for.  The only positive statement he ever made about his wisdom was to claim he knew the art of seduction.  Philosophy and Rhetoric are closely related: both rely on the art of persuasion, but philosophy struggles to find convincing arguments that hold true, so we may recognize the difference between faith and malignant ignorance. 

There is a paradox in our use of desire to struggle against desires, which can also lead to the abuse of reason: Augustine was haunted by the Problem of Evil. 

How does Plato understand the relationship between ignorance, faith, and reason? For him, reason allows us to know and understand the truth of the forms. This is the utmost struggle one undertakes in life. In his dialogues, Socrates is always presented as the “gadfly” (an aimlessly wandering, buzzing, annoying insect), pestering Athens’ citizens; his interlocutors begin pompously declaring their wisdom concerning the topic at hand and end up having their ignorance put on display before them as they quickly run away from Socrates and from further dialogue. Socrates was put on trial and sentenced to death partially for being so annoying. He confronted his interlocutors, the Athenians, with his pursuit of wisdom, and he prompted them to question themselves.  At his trial, he says, “the unexamined life is not worth living.”  This examination of life is the reflection upon the forms that are configured in nature, and also on the nature of knowledge and ignorance. Socrates also asks how we, as humans, should pursue the good life. 

Problem of Evil

The problem arises from the conflicts that come from three of God’s most essential attributes:

 

Specifically, the conflict comes from the questions that thus follow: If God is all-good, and evil exists, and he neither is nor does evil, how can he know evil?  If God is all-good, and evil exists, and he neither is nor does evil, then how can he be all-powerful?

Further, God’s omnipotence determines him to be the creator of everything.  However, God is also absolutely good; so, if he created everything, than he must have created evil, but if he is all-good, then he cannot have created evil.  Therefore, since there is evil in the world, either God did not create it, thus not all-powerful, or he did create evil and he is thus not all good. 

Thus, how can evil have come to be and still exist in the world without diminishing God?  

Some Key Ideas and Questions