St. Augustine and St. Thomas Aquinas: Philosophy and Theology

St. Augustine

Faith and Reason

St. Augustine believed that faith and reason must work together to lead to the truth. He opposed the idea that faith and reason were opposed, arguing that faith encourages reason. His view can be summarized as follows:

  1. Reason helps humans reach faith.
  2. Faith helps humans understand the mysteries of reality.
  3. Faith helps humans understand the principles established by faith.
  4. Reason accesses knowledge through the light that faith provides (doctrine of illumination).

Augustine believed that perfect models are only intelligible in the mind of God, but the soul can know them through the light that God provides.

Anthropology

Augustine believed that humans are composed of body and soul. Depending on the influence, his view of the human being varies. Under Platonic influence, the soul serves the body. Under Christian influence, he sees the human as a unity of body and soul, with the body as a temple for the soul. The soul is united to the body to dignify and rule it. For Augustine, each human being is unique. He believed that to know oneself is to journey inward and discover God, as our individual soul is what truly distinguishes us.

Theology

Augustine offered several arguments for the existence of God:

  1. Inner: When our soul internalizes, it encounters a truth that transcends it and whose origin cannot be itself. That truth is God.
  2. Perfection of the world: The perfection of the world requires the existence of a creator, which is God.
  3. Consensus gentium: As everyone acknowledges God as the creator of the world, God exists.
  4. Degrees of property: The existence of things that are more or less good implies the existence of the supreme good, which is God.

Augustine believed that the divine essence is ineffable and cannot be expressed in words. However, human reason can know the three attributes of God, which correspond to the three persons of the Trinity:

  1. God the Father: Corresponds to being, which is essentially pure and immutable.
  2. God the Son: Corresponds to truth (supreme knowledge).
  3. God the Holy Spirit: Corresponds to love, which gives us life.

Cosmology

Augustine believed that the divine mind always contains the ideas of everything in the world, and God uses these ideas to create reality. Human reason can only know two fundamental aspects of creation:

  1. It is timeless: Because God is timeless, time begins with creation.
  2. It is instant: Because God cannot change, God created all of reality from the beginning in a single moment. However, only some things were given actual existence, while others were given the potential to exist and develop over time (doctrine of seminal reasons).

Existence of Evil

Augustine believed that God is infinitely good, so evil cannot come from God. He explained that evil is a lack of being that affects finite and created beings. He distinguished three levels of evil:

  1. Metaphysical: In the universe, there are different levels of being. The less being something has, the more it suffers from deprivation, which is evil. However, the universe as a whole is in perfect harmony.
  2. Moral: Moral evil is sin, which stems from human malice. Evil is a wrong choice made by humans. The will, by nature, tends towards good. Sin is to prefer an inferior good, rejecting a higher one.
  3. Physical: Physical evil is identified with illness and death, which are consequences of original sin. The sinful soul corrupts the body. Humans redeem their sins through suffering in union with Christ.

Philosophy of History

In his book “City of God,” Augustine described two cities inhabited by different people:

  1. The heavenly city: Inhabited by those who love God to the point of contempt for themselves.
  2. The earthly city: Inhabited by those who love themselves so much that they despise God.

These two cities coexist and are in constant spiritual struggle. History has a linear design, beginning with creation and having two high points: the first coming of God the Son (Jesus) and the second coming, the end of history, with the triumph of the city of God and eternal salvation. Christians must maintain hope and a positive attitude towards difficult times. The State must recognize that it is a last resort.

Context

St. Augustine’s philosophy developed during the late fourth and first half of the fifth centuries AD. This was a turbulent era marked by the division of the Roman Empire, the decline of the Western Roman Empire, and the rise of Christianity. The classical world was in crisis, and the Middle Ages were beginning. Christianity, founded by Jesus of Nazareth and theorized by St. Paul, went from being a persecuted sect to the official religion of the Roman Empire. This led to the decline of paganism and the rise of a new era dominated by Christianity. Philosophically, Christian thought gained prominence. Christianity did not entirely reject classical philosophy but sought to synthesize it with Greek philosophy, as seen in Augustine’s use of Platonism to explain Christian doctrine. This period, known as the Patristic era, was crucial for supporting Christian dogma and combating heresies. It also saw a profound reflection on the relationship between reason and faith, with Augustine advocating for a mutually dependent relationship between the two.

St. Thomas Aquinas

Faith and Reason

St. Thomas Aquinas granted greater autonomy to philosophy than Augustine, basing it on principles accessible to natural reason, while theology is based on the truths of faith. Philosophy is the first science but does not offer salvation. The Christian philosopher does not use faith to do philosophy. Aquinas distinguishes between two orders:

  1. Nature: The human being as a natural creature, where reason stands out.
  2. Grace: The human being as a child of God. The order of nature is subordinate to that of grace.

Philosophy is an exercise of understanding the natural order, but understanding does not necessarily receive the light of God. The agent intellect possesses the intellectual light of God. Intelligence gives us access to God in both orders. Thus, theology is the foundation of philosophy. The truth of faith is superior to the truth of reason, but they cannot contradict each other. There are two types of truths of faith:

  1. Those that are above reason and cannot be proven, called mysteries of faith.
  2. Those that are accessible to reason and can be understood through philosophy. These are revealed by God.

Metaphysics

Aquinas expanded and modified Aristotle’s metaphysics. His most important doctrine is the analogy of being, which distinguishes between the act of being and essence. There are two types of substances:

  1. Material: Accessible to the senses and have two levels: substantial (matter related to form, potentiality and actuality) and accidental (matter determined by accidents).
  2. Immaterial: Pure forms or beings consisting of potency and act.

Entities created by God are essentially potential beings, but God is pure act of being by nature. God is being and identity, while being as an act is limited by essence. Creatures have borrowed being; only God is being by nature. The necessary being is one in essence, identified by the act of being. The contingent being is one in which its essence does not include the act of being. Immaterial creatures cannot cease to be, so they are immortal.

Existence of God

Aquinas presented five proofs for the existence of God, called the Five Ways. These are not articles of faith and can be demonstrated by reason. The Five Ways are different paths to rationally trace the existence of God. They follow four steps:

  1. Start with an observable natural phenomenon.
  2. Apply the principle of causality.
  3. Focus on the impossibility of an infinite regress of causes.
  4. Each Way reaches a certain terminus, which is God.

The Five Ways are:

  1. Motion: Things in the world move. Whatever moves is moved by another, but there cannot be an infinite chain of movers. The terminus is the Unmoved Mover (God).
  2. Causality: Nothing in the sensible world is its own cause. The final cause is not sufficiently explained by intermediate causes. There cannot be an infinite chain of causes. The terminus is the Uncaused Cause (God).
  3. Contingency: There are contingent beings, which could have not existed. If all beings were contingent, the world could not be explained. Beings are not merely possible. The terminus is the Necessary Being (God).
  4. Degrees of Perfection: Beings have qualities in varying degrees. All limited perfections are possessed, so they cannot all be infinitely possessed. The terminus is the Being in Essence (God).
  5. Teleology: Natural things act for an end. What happens in an orderly manner responds to a plan. Chance cannot be the cause of the universe. The terminus is the Ordering Intelligence (God).

Soul

Aquinas rejected Platonic dualism. The soul is the substantial form of the body and the principle of human operations. It has different faculties or active powers, which can be lower (shared with animals) or higher. His hylomorphic theory is compatible with the immortality of the soul, as there is a gradation in forms. If the material is exceeded, it can be known. Cognitive operations can be based on:

  1. The senses: If a body depends intrinsically on an organ, it cannot survive when the organ is destroyed. Senses have limited perception of form.
  2. The understanding: Can know all the forms of things. Depends on the brain accidentally.

Knowledge and Understanding

Human knowledge involves two types of understanding:

  1. Possible intellect: Receives intelligible forms and configures them as concepts.
  2. Agent intellect: Illuminates the possible intellect to draw out intelligible images and moves it to be updated by its operations. It has a particular character and is a light possessed in the natural order.

To acquire knowledge, four steps are involved:

  1. Intellection of individuals through the senses, which are stored as individual images, not universals.
  2. Abstraction: The transition from the individual to the universal. The intellect removes all individual characteristics and leaves only the essential, universal aspects.
  3. Elaboration of the concept: The possible intellect develops the concept as a universal.
  4. Judgment: The concept is applied to the phantasms.

Ethics

Aquinas’ ethics has a natural basis, founded on Aristotle. He considers happiness the object of ethics and politics and the most characteristic human pursuit. Aquinas adds that the ultimate end of life is supernatural and comes from the grace of God. Humans will be eternally happy in heaven. He also builds on Aristotle’s concept of moral virtue, which is a rational middle ground between two opposite vices, acquired through the repetition of good acts. Aquinas develops this with the theological virtues, which are aimed at God: faith, hope, and charity. Another concept is synderesis, which gives reason two uses:

  1. Theoretical: Based on the principle of contradiction.
  2. Practical: Directs action, and its first principle is that good is to be pursued as desirable. Synderesis can be formulated as: do good and avoid evil.

The human essence has three features, from which the main bodily inclinations and the precepts of practical reason derive:

  1. Substantiality: Humans tend to stay alive.
  2. Animality: Includes sexual orientation and the tendency to care for offspring.
  3. Rationality: Tends to know the truth and relate to other people.

Politics

For Aquinas, the state is good for human nature. As humans are social, society is the realm to achieve happiness. We must distinguish between the good of each individual and the common good. The latter is to meet the material, intellectual, emotional, and religious needs of human beings. He defines law as the order of reason towards the common good and distinguishes three types of law:

  1. Eternal law: The order of divine intelligence. God governs all created things.
  2. Natural law: Positive inclinations that represent God.
  3. Positive law: Human-made laws that should be based on natural law.

Context

St. Thomas Aquinas was a thinker of the thirteenth century, a period of cultural revival in Europe. This era saw the rise of towns, trade, Gothic art, universities, and the mendicant orders (Dominicans and Franciscans). The great European monarchies began to consolidate, and the bourgeoisie emerged. The politico-religious ideal of a universal Christendom led to clashes between the empire and the papacy. The Crusades and the Toledo School of Translators fostered cultural exchange between the Islamic and Christian worlds. Aristotle’s works and Averroes’ commentaries were introduced to Europe, leading to debates among thinkers. Some criticized them, while others, like Aquinas, sought to reconcile Aristotelianism with Christian faith. Scholasticism reached its peak in the thirteenth century due to these factors, the creation of universities, and the emergence of the mendicant orders. The prevailing philosophical currents were Augustinianism, Averroist Aristotelianism, and Christian Aristotelianism, with Aquinas being a key figure in the latter.