The existence of God has long been a subject of great interest to people around the world. Numerous theologians, philosophers and everyday observers have advanced arguments for and against the likelihood that an all-powerful Deity reigns over the universe.
Five of the most resilient arguments heard in this long debate came from the brilliant mind of thirteenth-century philosopher and theologian Thomas Aquinas.
Who Was Thomas Aquinas?
Thomas Aquinas (also known as Thomas of Aquin or Aquino) was an Italian Dominican priest of the medieval Catholic Church. The name “Aquinas” is not a surname, but rather a name given to him by virtue of his place of origin.
Born in A.D. 1225, Thomas would grow to become one of the foremost theologians in pre-Reformation Europe. Thomas was a prolific proponent of natural theology and was immensely influential in western thought.
Much of modern philosophy owes a debt of gratitude to Thomas’s writings.
Thomas Aquinas’s Five Proofs of the Existence of God
Building on the logic of legendary philosopher Aristotle, Thomas Aquinas outlined compelling reasons for people to embrace the existence of God. Thomas Aquinas’s arguments for God consisted of:
Argument from Motion
There is motion in the universe. Since nothing can move itself, an external agent or force is/was necessary to cause or instigate the motion that is in the universe.
Embracing Aristotle’s reasoning, Thomas Aquinas dismissed the possibility of an infinite regress of forces. There must be (in the words of Aristotle) an “unmoved mover.”
Argument from Cause
Based on the premises that every effect has a cause and that everything that begins to exist or happen is an effect, the cosmological argument holds that there must be an ultimate First Cause.
After all, an infinite regress of effects is nonsensical. An original cause had to start the train of effects.
Argument from Perfection
The universe contains a pyramid of beings (from simple, basic organisms to advanced organisms such as humans). This “ever-increasing degree of perfection” points toward a final being that must be perfect and ideal.
Argument from Design
The world contains an observable order or design. Such design cannot be attributed to the object or objects in question. There must be an external Designer to account for the complexity of life and the order of the universe.
Argument from Necessity
Everything that exists does so in relation to other things. Within this observed network of relationships, everything that exists is dependent on something else. However, an infinite regress of such relationships is contradictory and impossible. There must be a “necessary being” which is contingent on nothing else for its existence.
The Legacy of Aquinas’s Arguments
These five arguments for God’s existence have endured to become hallmark defenses of monotheism. These arguments (or variations of them) are in evidence in virtually every work of monotheistic apologetics.
Though they have been challenged by atheist writers over the centuries, none have been fully refuted. Their staying power is testament to their credibility, to the brilliant mind who conceived them, and the faith he embraced.