St. Thomas Aquinas'
St. Thomas Aquinas (1224-1274) was a Dominican priest,
theologian, and philosopher. Called the Doctor Angelicus (the Angelic
Doctor,) Aquinas is considered one the greatest Christian philosophers to
have ever lived. Two of his most famous works, the Summa Theologiae and
the Summa Contra Gentiles, are the finest examples of his work on
"The truth of the Christian faith...surpasses the capacity
of reason, nevertheless that truth that the human reason is naturally endowed
to know can not be opposed to the truth of the Christian faith."
First Way: The Argument From Motion
St. Thomas Aquinas, studying the works of the Greek philsopher
Aristotle, concluded from common observation that an object that is in motion
(e.g. the planets, a rolling stone) is put in motion by some other object
or force. From this, Aquinas believes that ultimately there must have been
an UNMOVED MOVER (GOD) who first put things in motion. Follow the agrument
1) Nothing can move itself.
2) If every object in motion had a mover, then the first object
in motion needed a mover.
3) This first mover is the Unmoved Mover, called God.
Second Way: Causation Of Existence
This Way deals with the issue of existence. Aquinas concluded that
common sense observation tells us that no object creates itself. In other
words, some previous object had to create it. Aquinas believed that ultimately
there must have been an UNCAUSED FIRST CAUSE (GOD) who began the chain of
existence for all things. Follow the agrument this way:
1) There exists things that are caused (created) by other things.
2) Nothing can be the cause of itself (nothing can create itself.)
3) There can not be an endless string of objects causing other objects
4) Therefore, ther must be an uncaused first cause called God.
Third Way: Contingent and Neccessary Objects
This Way defines two types of objects in the universe: contingent
beings and necessary beings. A contingent being is an object that can not
exist without a necessary being causing its existence. Aquinas believed that
the existence of contingent beings would ultimately neccesitate a being which
must exist for all of the contingent beings to exist. This being, called
a necessary being, is what we call God. Follow the argument this way:
1) Contingent beings are caused.
2) Not every being can be contingent.
3) There must exist a being which is necessary to cause contingent
4) This necessary being is God.
Fourth Way: The Agrument From Degrees And Perfection
St. Thomas formulated this Way from a very interesting observation
about the qualities of things. For example one may say that of two marble
scultures one is more beautiful than the other. So for these two objects,
one has a greater degree of beauty than the next. This is referred to as
degrees or gradation of a quality. From this fact Aquinas concluded that
for any given quality (e.g. goodness, beauty, knowledge) there must be an
perfect standard by which all such qualities are measured. These perfections
are contained in God.
Fifth Way: The Agrument From Intelligent Design
The final Way that St. Thomas Aquinas speaks of has to do with the
observable universe and the order of nature. Aquinas states that common sense
tells us that the universe works in such a way, that one can conclude that
is was designed by an intelligent designer, God. In other words, all physical
laws and the order of nature and life were designed and ordered by God, the
A more complete explanation of St. Thomas' Fifth Way about God as
Intelligent Designer can be seen on my web page dedicated to Paley's Teleological
Last revised 19 May anno Domini by P.Weiss