Aquinas’ Five Proofs
The Mystery of Creation
Christian Ed 10
Before we walk the path to enlightenment noble
students, please reflect on the following passage from
Paul to the Romans:
"The unseen things of God are visible through His
manifest works."
Rom. I: 20
Aquinas was inspired by this passage to examine God’s
works and prove to the skeptics that there is a God.
St. Thomas Aquinas argued that there are 5
ways to prove the existence of God…
The First Proof: The Prime Mover
 Consider a bouncing
ball. How did the ball
start bouncing? Did it
fall and if so what
caused it to fall? What
started all the action?
According to Aquinas,
“it is necessary to go
back to some first
mover, which is itself
moved by nothing--and this all men know
as God.”
The Second Proof: The First Cause
 Consider yourself and your family
history. You came to be because of
your parents and your parents came
to be because of their parents and so
on. But where does it begin?
 Aquinas explains, “if the chain were
to go back infinitely, there would be
no first cause, and thus no ultimate
effect, nor middle causes, which is
admittedly false. Hence we must
presuppose some first
efficient cause---which all call God.”
The Third Proof: Possibility and Necessity
 Consider things that exist beyond the realm of human control. How
did trees, animals, mountains, stars, and the sun come to exist?
What caused these things to exist? If it was a mere accident what
existed before the universe? If nothing, then nothing can come
from nothing.
 Thus, Aquinas argues, “there must be presupposed something
necessarily existing through its own nature, not having a cause
elsewhere but being itself the cause of the necessary existence of
other things---which all call God.”
The Fourth Proof:
The degrees found in things
 Consider the notion that
there are varying degrees of
love, goodness, and
perfection. Consider the
concept of heat. There are
certainly varying degrees of
heat.
 Aquinas points out, “fire,
which is the greatest heat, is
the cause of all heat.” The
cause of the greatest love,
goodness, and perfection is
who we call God.
The Fifth Proof: The Cosmos
 Examine the natural world
around you. Although it
appears to be chaotic at times,
nature is very structured.
Weather systems, oceans, the
solar system, time, it all has
structure. Who is responsible
for this structure? Who could
have designed such a plan?
 Aquinas saw this ordered
structure and argued, “there is
something intelligent by
which all natural things are
arranged in accordance with a
plan---and this we call God.”
Design of Our Solar System
The Earth is protected from
comets by the large outer planets
Established a unique continental crust,
which allows for recycling of minerals
through tectonic activity.
"Things are in motion, hence there is a first mover.
Things are caused, hence there is a first cause.
Things exist, hence there is a creator.
Perfect goodness exists, hence it has a sourcer.
Things are designed, hence they serve a purpose."
-- Thomas Aquinas
Another Perspective FOR God
Father Robert
Barron
“Why do we believe in
God?”
What 3 points does
Fr. Barron make?
Sometimes you just gotta have….
F-A-I-T-H !
 Both Aquinas and Fr. Barron
provide a rational proof for the
existence of God. However, it is
not enough to simply think you
know that God exists. You must
believe. If you pray to God and
contemplate on His numerous
gifts and works then He will reveal
Himself to you.
 But it takes time and it is difficult.
One of the ways God reveals
Himself to you is through your life
because you are part of God’s
creative plan.