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Why Does the Universe Exist?: The Leibnizian Cosmological Argument

Besides his interest in Christian philosophy, Gottfried Wilhelm von Leibniz (1646-1716) was one of the greatest mathematicians of western civilization.

Besides his interest in Christian philosophy, Gottfried Wilhelm von Leibniz (1646-1716) was one of the greatest mathematicians of western civilization.

Why does the universe exist instead of nothing? Gottfried Wilhelm Leibniz (1646 – 1716) pondered this question and formulated a cosmological argument to address it. The Leibnizian Cosmological Argument is but one of a group of cosmological arguments. According to Craig and Moreland (2003) there are three types of cosmological arguments. First, the Kalam Cosmological Argument seeks to establish that a first cause began the universe. Second, the Thomistic Cosmological Argument seeks a “Ground of Being” for the universe, and the Leibnizian Cosmological Argument seeks a sufficient reason for the existence of the universe. According to Leibniz, the universe must have an explanation for its existence. That explanation must be more than just a material cause, but rather a “sufficient reason” for why the universe exists.

The Principle of Sufficient Reason

We understand that every existing thing must have an explanation for its existence. Some things exist because they result from other things (that is, they’re contingent) while other things exist because they exist necessarily (that is, they exist by the necessity of their nature).

People, textbooks, and skyscrapers are contingent. They exist because someone else produced them. We exist because of our parents, textbooks exist because of writers and printers, and skyscrapers exist because of engineers and builders. However, some theorists of mathematics believe that numbers exist necessarily. For example, let’s take the value “two.” It seems silly to ask “where did ‘two’ come from”? (Not “two” as in the numeral, but “two” as a value regardless of what numeral we’re using). It wasn’t produced by a union of “one” and “three”!

How about God? Is he necessary or contingent? If there is a God, He would have to be a necessary being if He’s going to be the sufficient reason for why anything exists. When we speak of a “sufficient reason” we mean the “ultimate reason.”

Philosopher William Lane Craig Presents the Leibnizian Cosmological Argument at Wake Forest University


We can use the example of a row of dominoes. Let’s say you walk into a room where a series of dominoes are lined up and are knocking each other down, one after the other. If you walk in while the 9,999th domino is hitting the 10,000th one, you would observe that the material cause of the toppling of the 10,000th domino was that it was hit by the 9,999th domino. And you can predict that number 10,000 will hit and topple 10,001 and so forth. But knowing this chain of causation does not tell you why the dominoes are toppling in the first place. In other words, it isn’t “sufficient” to say “Well, the reason they're toppling is because domino number one hit number two, number two hit number three, number three hit number four and so forth. There had to be an event that set the chain of events into motion in the first instance. But, if you said, “They're John’s dominoes. He laid them out on the floor in the room, and he toppled the first domino” you have offered a sufficient reason for why they’re toppling.

If we’re going to be rational about explanation, we need a sufficient reason for the toppling of the entire chain of dominoes. Who put in place the series of dominoes and initiated their toppling in the first place? When it comes to the universe and what set it in motion, that “sufficient reason” is what Leibniz referred to as “God.”

But what if I said that the toppling of the dominoes has no explanation: “It’s just inexplicable”? Or what if I said “the dominoes necessarily exist”? Perhaps I might say, “We can’t know why the dominoes are doing what they’re doing.” Would you accept these explanations?

The Atheist Response

If we’re going to be rational, we can’t say that the universe exists without explanation. However, this is the explanation given by some atheists. That’s the kind of response we give small children when we don’t want to tell them where babies come from (“He was just….’born’”!). If the atheist wants to maintain rational integrity, he has to abandon the view that the universe “just exists” without explanation.

How about the universe? Does it exist necessarily like some theorists believe numbers and sets exist? Some atheists have said “yes,” however, given that the universe is a physical entity, this conclusion seems implausible. It seems more plausible that since the universe is a physical entity, it also had a cause. To exempt the universe from causation seems arbitrary since our uniform and repeated experience is that all other physical entities have causes. Why should the universe be the one physical entity exempt from causation?

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Many atheist will say “it’s just not possible to know with any certainty what is the sufficient reason of the universe.” This response strikes me as a capitulation to ignorance. Yes, we can say, “we cannot know with certainty.” But we’re not seeking certainty, but rather the best explanation for the existence of the universe. Surrendering the question without offering a discussion about possible hypotheses and their relative merit is a retreat from rationality, not progress toward it.

It also needs to be said that in order to say “we can’t know” there must be some basis of knowledge for the statement. We have to ask the atheist, “If you say that the universe lacks an explanation for its existence, how do you know this”? If you are ignorant of truth x, I doubt you have enough knowledge to know whether or not it’s possible to know truth x.


But why assume that the sufficient reason for the universe’s existence is God? The being that brought the universe into existence would have to be a timeless and immaterial being of maximal power. Such a being has been what orthodox Jews and Christians have referred to historically as “God.”

Here, I have sketched the basics of Leibniz’s powerful argument for the existence of God based on the contingency of the universe. The universe needs an explanation, a sufficient reason, to bring it into existence. The best explanation is that the universe came into existence from God.


J.P. Moreland and William Lane Craig. Philosophical Foundations for a Christian Worldview. Downers Grove, IL: InterVarsity Press, 2003.

© 2010 William R Bowen Jr


William R Bowen Jr (author) from New Bern, NC on September 25, 2010:

Thank you Ms Dee. I'm glad it was helpful.

Deidre Shelden from Texas, USA on September 25, 2010:

This is great to learn of Leibniz's well reasoned argument for pointing out to my doubting relatives! Bookmarking this one :)

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