* summarized from Edward Feser’s book, Five Proofs of the Existence of God,
Ignatius Press, 2017
1.
The Aristotelian Proof
Since
change actually occurs, and change is defined as the actualization of a
potential, there must exist something that can actualize potentials without
itself being actualized. This something
is purely actual because it lacks any potentiality. Any actualization of a
potential requires a cause, whereas what is pure actuality does not. This is the
“unmoved mover” of Aristotle, characterized as God.
2.
The Neo-Platonic Proof
Things that we experience are
composite; the ultimate cause of composites must itself be non-composite, or
absolutely simple. Composite things require a cause because there must be some
principle outside them that accounts for the composition of their parts. What
is non-composite has no parts to be put together, therefore could not be caused. Neither the universe, or even a multiverse
could be uncaused, necessary, or self-explanatory because they are composite.
3.
The Augustinian Proof
Universals,
propositions, possibilities, and other abstract objects must ultimately be
grounded in a divine intellect.
4.
The Thomistic Proof
For
any of the contingent things of our experience, there is a real distinction
between its essence and its existence.
Nothing like this could exist unless it was caused to exist by something
in which there is no such distinction. Something whose essence just is
existence need not have existence conjoined to its essence and therefore does
not need a cause. The universe, Big Bang, quantum events, or laws of nature
could not be uncaused causes. Only
something whose essence just is existence itself could be an uncaused cause.
5.
The Rationalist Proof
There
cannot be an explanation of the existence of any of the contingent things of
our experience unless there is a necessary being. The universe is contingent
rather than necessary and thus could not provide an ultimate explanation.
