Augustine and Aquinas: Faith, Reason, and Existence

Augustine

The Knowledge of Faith

St. Augustine created the first great synthesis between Christianity and Platonic and Neoplatonic philosophies.

The Inner Search for Truth

To know, the process starts with a return to yourself. It was argued, in the interpretation of the Platonic soul, that sensitive knowledge has only a relative and mutable value; it is a mere reflection of immutable ideas. True reality is only accessible from within.

Both sensitive knowledge and the rational part, Augustine calls the “lower reason.” Above it, the “higher reason” reaches the true meaning of the world because of faith. This is a twofold process in which rational inquiry is animated by the light of revelation.

Truth is internal and transcendent at the same time. It originates in the denial of the outside world and doubt, and ends at the opening of God and the certainty that stems from His evidence. It is the discovery of immutable truth. For this, we need the help of faith.

The Relationship Between Faith and Reason

Christian Attitudes About Truth and the World

For the Greeks, there was no absolute and evident truth, and it was reached after a long rational process. In contrast, Christianity categorically stated that truth was unique, absolute, and enforceable by human reason because of Revelation. Greek philosophy did not accept that something could come out of nothing, or that there was only one God. A true Christian explained the origin of the world as creation out of nothing by a single all-powerful God. Created nature guides the salvation of mankind.

Two positions arose around this debate:

  • Confrontation, as expressed by the conviction that faith is stronger when supported by reason.
  • Reconciliation: Augustine believed that it is not possible to believe without reason.

Policy: The Two Cities

A Philosophy of History

There are two models of society. Augustine called them cities: the City of God and the City of Man.

The City of God comes to be identified with the Church, considered in its invisible and spiritual dimension. It includes every human being guided by the love of God. Augustine interprets history as guided by the action of God through his Church. He saw in the fall of the Roman Empire, considered politically perfect by the Romans, a sign of the crisis of the City of Man, given over to selfishness.

Aquinas

Averroes

He presents a synthesis of Aristotelian thought. The controversial questions that have arisen are the following:

The Eternity of the World

Averroes considers the world eternal because the principle of motion is eternal.

Immortality is Not Personal

Averroes says that the active intellect is separate and immortal, but the possible understanding is only the capacity that receives sensations and is mortal.

Of Double Truth

He distinguishes three categories of spirits:

  • Philosophers, characterized by demonstration, which requires certain knowledge.
  • Theologians, characterized by dialectic.
  • Men of faith, characterized by exhortation.

Averroes in America: The arts faculty of the University of Paris advocated for Aristotle’s education as an axis. Pope Gregory IX condemned it. After several fights, the defenders defended themselves from criticism with the doctrine of double truth: the truth of faith and the truth of reason. They saw doctrines about the origin of the world and the immortality of the soul as the truth. This movement is called Latin Averroism.

Thomistic Ways

St. Thomas developed five ways that are a posteriori demonstrations of God’s existence:

The First Way, or the Unmoved Mover

It is a fact of experience that things move. Everything that moves is moved by another. The number of engines that move one another cannot be infinite. Therefore, there is a first mover that is not moved, and this is God.

The Second Way, or Efficient Causes

From the fact that everything is a cause, it is, in turn, the effect of a previous cause. We cannot continue indefinitely in the series of causes. Therefore, there is an uncaused first efficient cause: God.

The Third Way, or Contingent Beings

There is generation and corruption in the world: things begin to exist and cease to exist. If something has a limited time, there was a time when nothing existed. For this, we call on God.

The Fourth Way, or Degrees of Perfection

There are degrees of perfection in human beings: we see that some are more or less good, true, and noble than others. Therefore, there is a supreme being that has all perfection in its highest degree and is the ultimate cause of all perfection.

The Fifth Way, or Order in the World

It is based on the objective in nature. We see certain things that lack knowledge working towards an end, always watching to get what they need. Therefore, there is an intelligent being that directs all natural things to an end, and we call this being God.