THE FIVE ARGUMENTS OF NATURAL THEOLOGY

“Natural theology” is a branch of theology that seeks to provide justification for belief in God’s existence without the use of scripture.

Each of these five arguments for the existence of God is an independent piece of evidence that does not rely on the others for its justification.

Because each is independent, logic requires that we must also consider the cumulative effect of these arguments taken together.

A COSMOLOGICAL ARGUMENT

A “cosmological argument” presents evidence for the existence of God based on the physical reality we see around us.

THOMAS AQUINAS ASKED “WHAT CAUSED THE UNIVERSE?” AND CONCLUDED THAT “GOD WAS THE UNCAUSED FIRST CAUSE”

Over centuries, the most quoted arguments would be the second and third of Thomas Aquinas’ five arguments to demonstrate God’s existence.

Aquinas asked the question, “What caused the universe?” He began with his guiding principle that “everything has a cause”; everything is part of a “series of causes.” For example, my parents caused me, their parents caused them, etc., going back in time. This is called a “causal regression” because it goes backward in time until we come to the very “first cause” of everything.

Echoing Aristotle, Aquinas theorized that the entire universe goes back to an original God or creator, the “Uncaused First Cause.” Aquinas said that God himself was “uncaused” because nothing existed prior to God. If God were “caused,” it would require that some state of affairs existed prior to him, but that is not the case. So God existed into the eternal past; the universe did not.

G.W. LEIBNIZ ASKED, “WHY IS THERE SOMETHING RATHER THAN NOTHING?” AND CONCLUDED THAT THERE MUST BE A “METAPHYSICALLY NECESSARY BEING”

Regarding cosmological arguments, Gottfried Wilhelm Leibniz presented a better line of reasoning than most. Leibniz asked a different question: “Why is there something rather than nothing?” He began with his guiding principle that “nothing happens without a sufficient reason” (called the Principle of Sufficient Reason).

Leibniz said it was not as helpful to look at prior causes like Aquinas did because a causal regression is just a description of past states and does not explain “why.”

What is the “universe”? The “universe” includes all space-time reality, including all matter and energy. Before the universe came into existence, there was no time and no space, just God and his will.

Leibniz was NOT seeking for a cause, but instead he was searching for an “explanation for why we exist.” Aquinas followed a “causal regress” back to an “uncaused first cause.” Leibniz followed a “sufficient reason for existence” back to a “self-explanatory being” or “greatest conceivable being.”

Aquinas searched for a “cause,” and Leibniz asked “why?”

People sometimes mix Aquinas’ and Leibniz’s arguments together, mistakenly concluding that Christians believe God was “self-caused.” But both Aquinas and Leibniz would say that’s impossible because things don’t cause themselves and no state of affairs existed before God. Rather, God is simply an “uncaused” and “metaphysically necessary” being.

CONCLUSION

Aquinas’ tracing a causal regress back to an “uncaused first cause” has served as an excellent cosmological argument for the existence of God from the 1200s AD until today.

In the 1600s, G.W. Leibniz made an even stronger case by asking his question, “Why is there something rather than nothing?” and by suggesting his guiding principle that “Nothing happens without a sufficient reason.”

We will explore the argument by G.W. Leibniz further in the next few blogs.