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3 Arguments for God’s Existence

Perhaps the most fundamental question any religious believer can ask is: “Does God exist?” It’s time we find good answers.

This is the third essay of 18Forty’s new “Faith in Reason” series with Rabbi Steven Gotlib, released the last Sunday of every month. Sign up for it here, and read the second essay here.

Perhaps the most fundamental question any religious believer can ask is: “Does God exist?” Many have argued that without such a belief undergirding religious commitment, all is for naught. Christian apologist William Lane Craig, for example, argues in Reasonable Faith that “if there is no God, then man and the universe are doomed… It means that life itself is absurd. It means that the life we have is without ultimate significance, value, or purpose.”

Rav Aharon Feldman of Baltimore’s Ner Israel Rabbinical College takes a more pragmatic approach, writing in The Eye of the Storm that “belief in God makes it impossible to conclude that one’s personal interests are more important than others, or that one may harm someone who stands in the way of fulfilling those interests… why is not every self-centered atheist violent? Only because the strictures of his society and his upbringing do not permit him to be so.” 

Of course, as we discussed in our previous installment, pragmatic concerns such as this may impact what we want to believe, and push us in particular directions out of the gate, but are not complete arguments by the standards of rational logic. This essay will examine the primary philosophical arguments for God’s existence to keep these sorts of concerns out of the picture as much as possible. We will focus on the three most popular arguments—cosmological, teleological, and ontological. 

One note, before we begin: Many of the works cited below are from Christian philosophers who utilize them for other conclusions. I will address this in a future essay, but for now, we are accepting their arguments for God’s existence without accepting their arguments for Christianity.

Is Belief Basic?

One may argue, as we saw in my last essay, that belief in God can simply be taken for granted without any need for formal arguments at all. Alvin Plantinga, for example, has argued in Reason and Belief in God and elsewhere that assuming “theism is rationally acceptable only if there are good arguments” is a category error. I’ll explain what he means. 

Plantinga’s perspective treats belief in God as a basic—a belief that people are entitled to take for granted even without firm evidence—and it’s quite a popular position. If one is comfortable accepting it, there is relatively little work needed. In his book, The Jewish Idea of Religion and Theology, Sol Roth explains the difference between religious philosophy and theology as the former being scientific—accepting religious claims “as premises which need to be validated”—while the latter takes such claims for granted as axioms, without needing “proof,” and is only interested in expanding their meaning. In Roth’s words “the difference between premises and axioms is that axioms are not subjected to doubt or the need for verification; they are accepted as absolutely true. Premises on the other hand require verification.” Roth continues to note that engaging in Jewish theology “accepts [God’s] existence dogmatically and undertakes to expand on the meaning of the axiom by, for example, exploring His attributes, while philosophy of religion seeks to demonstrate its truth.” 

This series treats the question as philosophical rather than theological. That is to say that while readers are welcome to accept Plantinga and Roth’s framing, this series will not take God’s existence, revelation, Jewish chosenness, and the like for granted but will seek to establish verification for them from the ground up. 

This is because Yehuda Gellman and others have demonstrated that arguments rooted in personal experience and appealing to basicality are not universally compelling. One person’s reported experience cannot in and of itself convince someone who has not shared that experience. As such, this essay will not seriously consider these sorts of arguments, despite them being well within readers’ theological toolkits. Nor will we discuss arguments from morality, which will be addressed in our next installment. 

The Cosmological Argument

Cosmological arguments generally assume God to be the First Cause in a chain of causation leading to this very moment. If you have ever asked yourself “What created the materials that started the Big Bang?” or the like then you’ve engaged in a cosmological argument. Perhaps the most popular version is referred to as the “Kalam Cosmological Argument”:

Premise 1: Everything that has a beginning comes to exist by virtue of an external cause. 

Premise 2: The universe has a beginning.

Conclusion: The universe has an external cause. 

One weakness of this argument is that it only proves God if “God” is defined rather minimally. Rabbi Dr. Sam Lebens points out in Philosophy of Religion: The Basics that “even if all we mean is the creator of the universe, for all this argument tells us, that being may have ceased to exist upon giving birth to the universe. Surely, we want a proof that God still exists!” 

Maimonides’ version escapes that criticism. He wrote in his Guide for the Perplexed that “every physical and transient form must be preceded by another such form” and that “it is through the existence of God that all things exist, and it is He who maintains their existence by that process which is called emanation.” This is explained more clearly in the Mishneh Torah: 

The foundation of all foundations and the pillar of wisdom is to know that there is a Primary Being who brought into being all existence. All the beings of the heavens, the earth, and what is between them came into existence only from the truth of His being:

If one would imagine that He does not exist, no other being could possibly exist. 

If one would imagine that none of the entities aside from Him exist, He alone would continue to exist, and the nullification of their [existence] would not nullify His existence, because all the [other] entities require Him and He, blessed be He, does not require them nor any one of them. Therefore, the truth of His [being] does not resemble the truth of any of their [beings]. 

To Maimonides, then, God is not only the first cause in a chain of causation but is the foundation upon which all rests. We know that God still exists because, otherwise, nothing else would.

The greatest weakness of the Maimonidean Cosmological Argument is that it says absolutely nothing about God’s nature. Most Jews, indeed most theists, assume like Lebens that God is “at least this: a supremely good and intelligent agent, powerful enough to bring this universe into being, and to govern its evolution, in accordance with Its will.” Many scholars of Maimonides, though, have argued that his God is much less personal. In an article entitled Maimonides’ Theology (published in the Cambridge Companion to Jewish Theology), Dr. Daniel Rynhold writes as follows: 

There are those who believe in a personal God who intervenes and controls the world in some engaged manner. The belief in that type of God is their reason for engaging in their religious practices, and, in the absence of that theological foundation, they would view their religion as baseless, and it is not difficult to see why. If God is not viewed personalistically, we have all manner of problems with notions such as miracles, providence, and petitionary prayer, not to mention God’s direct communication of mitsvot to Moses… Yet there are those for whom that notion of God is deeply problematic. It might even undermine religious practice. How, for example, can such a God avoid being impeached by the problem of evil? Why, it might be asked, would an interventionist God choose not to intervene to prevent some of the greatest acts of destruction, both natural and moral, in human history? …For Maimonides, God is the source of eternal truth, and such truth is the ultimate value, not the satisfaction of our self-interested desires, tethered as they are to the fleeting temporal occupation of our material bodies. Whether God has the capacity to intervene in the world to further those interests should be of no concern to an individual who recognizes the true intellectual perfection for which humans ought to strive.

There is much work to be done, then, to get from the philosophical God of Maimonides to what most would think of when attempting to envision the God of the Torah. 

The Teleological Argument 

Another popular form of argumentation is teleological arguments or “arguments from design.” The basic argument goes like this: 

Premise 1: The universe bears the marks of design.

Premise 2: Objects that bear the marks of design have a designer. 

Conclusion: The universe has a designer. 

Some may be familiar with this argument from the Chazon Ish, who wrote in his Sefer Emunah U’Bitachon that one “reflects upon various aspects of the world, and sees enough to show him clearly that the world was built according to a calculated plan, as if an expert engineer made a blueprint of the world before it was created: insurmountable obstacles presented themselves at every step, and the great energy of this engineer enabled him to remove them all.” The human eye is particularly marvelous: 

The Planner saw that man would not be able to wear the crown that was bestowed upon him—as the jewel of creation—without detailed information about the contents of the world, from the inanimate to the flora, to objects of all kinds. Without this information the machine known as man would have no life. So the Planner considered this, and invented an apparatus in which everything in the world would make an impression by way of light—each object in its own particular way. Two such apparatuses were placed by Him in man’s face: one on the right and one on the left. We are in the habit of calling these apparatuses the right eye and the left eye.

The Chazon Ish goes on to employ this logic to show how the rest of the human body “is glorious and wonderful,” but the eye was long said to be “irreducibly complex” in that it would have required an intelligent designer as opposed to natural selection. Unfortunately, this argument no longer holds up, as explained by Jerry Coyne in his book Why Evolution is True

Darwin… surveyed existing species to see if one could find functional but less complex eyes that not only were useful, but also could be strung together into a hypothetical sequence showing how a camera eye might evolve. If this could be done—and it can—then the argument that natural selection could never produce an eye collapses, for the eyes of existing species are obviously useful. Each improvement in the eye could confer obvious benefits, for it makes an individual better able to find food, avoid predators, and navigate around its environment. 

Contemporary arguments for irreducible complexity involve cells. Recent work by James Shapiro implies that even single cells possess primitive decision-making capabilities, leading Shapiro to conclude that “it can reasonably be argued that cell cognition and intercellular communication are central to all levels of life.” He is quick to note elsewhere, though, that “there is no reason to believe that unsolved problems will remain without naturalistic explanations indefinitely.” 

A more compelling teleological approach is the “cosmic fine-tuning argument.” Sean Carroll summarizes it well in The Big Picture

The idea is that conditions—anything from the mass of the electron to the rate of expansion of the early universe—are fine-tuned for life’s existence. If these numbers were just a little bit different, the argument goes, we wouldn’t be here to talk about it. That makes perfect sense under theism, since God would want us to be here, but might be hard to account for under naturalism. In Bayesian language, the likelihood of life appearing in the universe might be large under theism, and small under naturalism. We can therefore conclude that our very existence is strong evidence in favor of God. 

Caroll acknowledges that this is “the best argument we have for God’s existence” and many (including the late Christopher Hitchens) agree. Plantinga, however, does not think the argument is all that it is cracked up to be. He explains why in his book God and Other Minds: A Study of the Rational Justification of Belief in God

In arguing that God exists, the theist typically means to argue for a proposition equivalent to a conjunction of which the following are conjuncts: 

    1. The universe is designed
    2. The universe is designed by exactly one person
    3. The universe was created ex nihilo
    4. The universe was created by the person who designed it. 
    5. The creator of the universe is omniscient, omnipotent, and perfectly good. 
    6. The creator of the universe is an eternal spirit, without body, and in no way dependent on physical objects. 

Now we can put the objection as follows: The teleological arguer may have some evidence (not very strong, perhaps, but not completely negligible) for A; but with respect to B-F our evidence is altogether ambiguous. In the case of propositions B-F our total evidence affords in each case an argument against it as strong as it yields for it. 

Others, though, think differently. Philip Goff proposes what he calls the Value-Selection Hypothesis in his new book Why? The Purpose of the Universe. He argues that “certain of the fixed numbers in physics are as they are because they allow for a universe containing things of significant value.” This led him to develop a view called teleological cosmopsychism in which 

the fundamental building blocks of reality are not particles but universe-wide fields, and that particles are simply local vibrations within these fields… the fundamental forms of consciousness underlie these universe-wide fields, and… a fundamental mind is the bearer of those fields: the universe itself.

This leads to a picture of the universe where “each moment, the universe is pushing to maximize the good, but under quite severe constraints as to what it is able to do.” Goff rejects traditional theism due to the Problem of Evil but also makes a stunning acknowledgment: 

If, during the first split second of time, the universe fine-tuned itself in order to allow for the emergence of life billions of years in the future, the universe must in some sense have been aware of this future possibility, in order to act in such a way as to bring it about. To account for this, we can attribute to the universe conscious awareness of the full possible consequences of each of the options available to it. (My emphasis) 

The model Goff ends up with is strikingly consistent with the Maimonidean understanding of God as a force that once began and now emanates through the cosmos while remaining fundamentally unknowable, with attributes only describable in the negative. 

Many, though, see such a minimal theology as problematic by eliminating Divine personality from the equation. Plantinga responds strongly to such approaches in his book Warranted Christian Belief

The idea, so far as I can grasp it, seems to be this… it is a good idea to continue to use the term ‘God’ and, in fact, to continue to utter many of the very same words and sentences as those who believe in God: done properly, this will promote human flourishing. How, exactly? Perhaps as follows. We realize, first, that there is probably no such person as God. We are then free to select a concept/image ‘God’ and associate it with certain properties—existence and transcendence, perhaps—and use that symbol to symbolize such as that the world is hospitable, to at least some degree, to to distinctly human aspirations, goals, needs, and desires. We are to say such things as ‘God is real,’ meaning that in fact there are forces in the world that contribute to human flourishing… You can thereby patronize the person in the pew (who has not reached your level of enlightenment) but without paying the cost of unduly disturbing her. The fact is such double-talk is at best confusing and deceptive, contributing only to misunderstanding, dishonesty, and hypocrisy. 

Proponents of such views may have what to rely on, though. Rynhold, as we saw above, wrote that there may be bigger philosophical problems with belief in a traditional God and that perhaps this question boils down to the fact that “people have different religious sensibilities, for want of a better term, and those sensibilities render very different views of God convincing.” 

If one’s religious sensibilities point towards a God like that described by Goff and certain readings of Maimonides then this argument has much room for success. If, however, one’s sensibilities require a personal God who is deeply involved in the world, the Problem of Evil must be dealt with before either the Cosmological or Teleological arguments can apply. 

The Ontological Argument

Ontological arguments are the most philosophically complex of the major ones. They are often jokingly referred to as “armchair arguments” because they presume that you can prove that God exists without even getting up! The strongest formulation was presented by Plantinga in his book The Nature of Necessity. It goes like this: 

Premise 1: If a being is unsurpassably excellent, then that being must be great in every possible world. 

Premise 2: A being that is maximally great in every possible world is necessarily maximally great. 

Premise 3: A being cannot be maximally great without existing in our world (and in every other possible world). 

Premise 4: Whatever is necessary is actually necessary. 

Premise 5: It is possible that there is an unsurpassably excellent being, call it “God.” 


    1. It is possible that God is maximally great in every possible world. 
    2. It is possible that God is necessarily maximally great. 


    1. God is necessarily maximally great. 
    2. God actually exists.

The “possible worlds” mentioned above refer to possible ways that the world we inhabit could have been. If God is maximally great, then God must exist in every possible way the world could have been. Therefore, God must exist in our world. Lebens writes that if this argument works, then “we don’t just have reason to believe in God, we have a logical proof that He exists, not just with omnipotence and intentions, but with every conceivable perfection.” Unlike the other arguments, this one successfully “demonstrates the existence of something that’s uncontroversially akin to the God of classical religions.” Plantinga, though, clarifies that this argument “isn’t a proof” : 

it must be conceded that not everyone who understands and reflects on its central premise—that the existence of a maximally great being is possible—will accept it. Still, it is evident, I think, that there is nothing contrary to reason or irrational in accepting the premise. What I claim for this argument, therefore, is that it establishes, not the truth of theism, but its rational acceptability.

Plantinga’s argument, known in philosophy as the “Modal Ontological Argument,” then provides proof for those who are already willing to accept the possibility that God exists, but at most only defends the rationality of such a view to those who are unable or unwilling to accept its possibility. 

So, Does God Exist?

This essay has examined the three most popular arguments for God. 

Lebens acknowledges that none of them “can serve as a decisive proof for the existence of God” and that, on their own, they “only support the existence of a being with some of the attributes commonly associated with the God of various religions.” If one assumes, like certain readings of Maimonides, that God need not have every attribute traditionally associated with Him, this does not present a challenge. If, however, one demands proof of a traditional personal God then the only argument that gets close on its own is the ontological argument, which presupposes God’s possibility. It is for this reason that Lebens argues, like Plantinga, that the strongest case for God can perhaps be made by “the argument from so many arguments.” That is to say that “the arguments collectively add weight to the proposition that there is one being (and, for reasons of economy, only one being), who is powerful, knowledgeable, just, and desirous of a relationship with humanity.”

Taken together, one can also make a case that these three arguments naturally combine: The cosmological argument can demonstrate a cause of the universe; the teleological argument can demonstrate intentionality; and the modal ontological argument can get the rest of the way to traditional theism. One may then perhaps conclude like atheist Graham Oppy in his book, Arguing about Gods, that “it possible to allow that there is a wide range of reasonable views about the existence of orthodoxly conceived monotheistic gods” while also acknowledging that “no argument that has been constructed thus far provides those who have reasonable views…with the slightest reason to change their minds… theism and non-theism are both reasonable responses to the evidence that people have.”

As discussed in our previous entry, though, the aim here is not to provide proof of God, but merely a preponderance (50% credence) of evidence. It is my contention that the cumulative weight of the three arguments we’ve examined provides a preponderance if one is willing to accept a “Maimonidean” theology. The strongest argument against a traditional personal theology is the Problem of Evil and Suffering, which will be addressed in our next installment. 

Recommended Reading

Philosophy of Religion: The Basics, by Samuel Lebens

This is a thorough and accessible overview of the philosophy of religion as a field, highlighting every major point of conversation. The argument summaries in this essay largely come from this book.

Why? The Purpose of the Universe, by Philip Goff

Philosopher Philip Goff explores how the universe could be imbued with purpose. While he does not end up with traditional theism, his approach leans strongly in that direction. 

Maimonides: Life and Thought, by Moshe Halbertal 

Here is an acclaimed biography and introduction to the thought of Maimonides, addressing several different ways of interpreting the great philosopher.

Rabbi Steven Gotlib is Marketing Manager at RIETS and Director of JET Ottawa’s Capital Jewish Experience.



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