Aquinas’ Philosophy: Reason, Faith, and the Existence of God
The Philosophical System of Saint Thomas Aquinas
The philosophy of Saint Thomas Aquinas was heavily influenced by Aristotle. He concluded that the proper object of our knowledge capabilities are sensible objects.
To reach the knowledge of God, one must begin with sensitive objects. From this knowledge, Aquinas derived ethical and political proposals.
Saint Thomas had to achieve three objectives:
- Establish a clear distinction between philosophy and theology. Only then may it be noted that mutual aid can be provided.
- Establish a system that coherently integrates all known doctrines.
- Establish a basic principle to harmonize the Christian version of the world and man with the Aristotelian version.
Relations Between Philosophy and Theology
Distinction Between Philosophy and Theology
As a good Aristotelian, Thomas argued that nature threatens to prevent the right to develop its full potential, especially that of reason.
The human mind, through the senses, gives us some knowledge. Only reason can endorse philosophical truths: it has its origin.
At the same time, as a believer, Thomas admits truths derived from revelation, that is, the authority of God. The truths of theology are rooted in faith in God who has revealed them. Only faith can attest to them.
Aquinas argued for a clear distinction between philosophy and theology, as their different origins implied a different perspective. Saint Thomas solved this by discarding the negative aspects found in each of the positions taken on this matter.
Controversy with Other Positions
Saint Thomas Aquinas criticized especially three extreme positions:
- For the anti-dialectical or mystical, he reminded them that human beings, endowed with reason by God, must use it to gain knowledge.
- For the dialectic, he insisted there are revealed truths that cannot be understood only by the light of reason.
- On the doctrine of double truth, Thomas was emphatic: reason is imposed as an inescapable law of contradiction. To accept a truth that is false in philosophy and true in theology is irrational. God is the Creator of everything, and it is inconceivable that He would have created an irrational world. Truth is one and cannot change according to the circumstances that arise.
- As to Augustine and, above all, to Saint Bonaventure, the problem that arises relates to the acceptance or rejection of Aristotle. Saint Bonaventure rejected Aristotle because his doctrines are irreconcilable with Christianity. In addition, the teachings of a pagan cannot be used to guide the Christian in his approach to the biblical God.
Mutual Aid Between Philosophy and Theology
Philosophy helps theology because it shows the preambles of faith, that is, it shows that God exists and that He is wise and true.
For its part, theology helps philosophy because it opens unexpected horizons of knowledge for reason. But above all, because it builds the strength of philosophical truths.
God and His Attributes
Saint Thomas Aquinas departed especially from Aristotle. Aristotle considered the Prime Mover as the final cause of motion without reference to created things, a closed pure act on the knowledge of Himself. The Unmoved Mover does not create the world because both the raw material and substantial forms are eternal.
The Existence of God is Not Obvious but it Can Be Shown
Need to Prove the Existence of God
Knowledge begins with the senses, and they do not manifest the existence of God unless it is in a vague and confusing way. If we were able to capture the essence of God, as we said, we would know His existence. The existence of God is self-evident, but not obvious to us.
Opportunity to Demonstrate the Existence of God
Saint Thomas said it is possible to prove the existence of God if you follow the right path. To this end, he established two types of demonstration:
- That which goes from cause to effect is called a priori (from what is above) because the causes are prior to the effect.
- That which ranges from the effects to the causes: it is called a posteriori.
Demonstrating the Existence of God: The Five Ways
The five ways of the Thomists always split a fact of experience that has to be explained in some way and that to do so, it necessitates the existence of any of the attributes which we all ascribe to God.
Adopt the model of the first track. In it, Thomas made the following observation: there are things that move (for example, my arm). Everything that moves is moved by another (because, otherwise, it would move itself, which is impossible because it would give something that it does not have), there is no process to infinity in the number of engines and moving it, if any, there would be a first mover, not a second or a third… and my arm would move, but my arm moves. Therefore, by way of conclusion, there is an unmoved mover, a first motor to which all call God.
As the structure of all routes is common, it can be summed up in the box above.