As a theologian and apologist who regularly offers a cumulative case for the existence of God, I am often asked to disclose my favorite argument in my repertoire. Indeed, near the end of a good Q&A session, where all kinds of questions and objections are raised, I can count on someone asking me what I take to be the best argument. This is often the one question that “stumps” me.
Although I have made a commitment to “never be stumped by the same question twice,” this question often leaves me confused and speechless. This is because I often vacillate between my list of favorites. I wake up on Monday and the Kalam is my favorite. I wake up on Tuesday, and the FreeThinking Argument is my fave! Then, on Wednesday, I seem to like the Moral Argument the best. Out of the “couple dozen arguments (or so,)” who knows what argument is going to get the nod on Thursday, Friday, or Saturday (Sunday is always reserved for the historical evidence for the Resurrection of Jesus)!
With that in mind, consider my typical “Top 6” arguments for the existence of God, and a quick summary of each (in no particular order).
#1- The Kalam Cosmological Argument
- Whatever begins to exist has a cause.
- The universe began to exist.
- Therefore, the universe has a cause.
The two premises are rather non-controversial and supported both philosophically and scientifically. Moreover, the argument says nothing about the existence of God. However, once one begins to understand exactly what is meant by “the universe” then one quickly sees how this argument reaches conclusions with theistic implications.
This is because the universe is typically described as the space-time universe, and/or, “all nature, space, and time.
If all nature began to exist, then whatever caused all nature must be something other than nature. This is exactly what philosophers refer to as “super-natural.” If space began to exist, then the cause of all space had to exist apart from space. This means that the cause of the universe is immaterial (since matter cannot exist apart from space), and thus, a non-physical kind of thing. Perhaps it should be described as a “spiritual substance.”
If time began to exist, then whatever caused moments to begin passing had to have been in a timeless state (where moments are not passing). But this means that whatever caused time, must have existed in a timeless state. But if the cause of time is timeless, then this means that the cause of time is “eternal” without beginning (because beginnings require time).
And since “apart from time things don’t happen,” the only way this causal power could actualize the universe would be if it CHOSE to do so – that is to say, it had to be a “free will kind of choice.” This means that the cause of the universe possesses volition. And since persons are the only kinds of things with the freedom to choose, we can decipher that the cause of the universe is a personal being.
So, after thinking logically about an argument which is supported scientifically, we seem to be left with an enormously powerful, supernatural, immaterial, eternal, volitional, and personal cause of the universe.
This sounds exactly like God.
For more on the Kalam Cosmological Argument, click here.
#2- The Moral Argument
- If God does not exist, then objective moral values and duties do not exist.
- Objective moral values and duties do exist.
- Therefore, God exists.
If the two premises of this deductive syllogism are true, then the conclusion must be true. So, the question is raised, why think the premises are true?
Think about it: If God does not exist, then humanity was not created on purpose or for a specific purpose. If that’s the case, and humans are a mere accident of nature, then there is no objective standard (true apart from human opinion) in which humans ought to approximate. We are nothing more than “dust in the wind.” You are entitled to your subjective opinion, and Hitler is equally entitled to his.
This doesn’t seem right.
However, if God exists everything changes. This is because if God created humanity on purpose and for a specific purpose, then there would be objective facts about humanity irrespective of the subjective opinions from humanity. These objective facts would include moral facts – how we ought to live and treat each other.
It follows that if Hitler was really wrong – in an objective sense – and violated “the Law above the law (as expressed at the Nuremberg Trials) – then God exists! If racism is really wrong (as opposed to mere personal opinion), then God exists. If kidnapping, rape, and murder are all objectively wrong, no matter what anyone subjectively thinks to the contrary), then God exists.
It seems intuitive that nazism, communism, racism, kidnapping, rape, and murder are really wrong in an objective sense.
Therefore, God exists!
Fore more on the Moral Argument, click here.
#3- The Fine-Tuning Argument
Consider what I take to be the best formulation of the Fine-Tuning Argument:
1- The fine-tuning of the universe is due to either physical necessity, chance, or design.
2- The fine-tuning is not due to physical necessity or chance.
3- Therefore, the fine-tuning of the universe is due to intelligent design.
By the Fine-Tuning Argument reference is being made to certain constants and quantities found in the universe, which—if they were to have only the slightest deviation—would make both the existing universe and life itself impossible. William Lane Craig, who has championed this argument, provides the following examples:
* Speed of Light: c=299,792,458 m s-1
* Gravitational Constant: G=6.673 x 10-11 m3 kg-1 s-2
* Planck’s Constant: 1.05457148 x 10-34 m2 kg s-2
* Planck Mass-Energy: 1.2209 x 1022 MeV
* Mass of Electron, Proton, Neutron: 0.511; 938.3; 939.6 MeV
* Mass of Up, Down, Strange Quark: 2.4; 4.8; 104 MeV (Approx.)
* Ratio of Electron to Proton Mass: (1836.15)-1
* Gravitational Coupling Constant: 5.9 x 10-39
* Cosmological Constant: (2.3 x 10-3 eV)
* Hubble Constant: 71 km/s/Mpc (today)
* Higgs Vacuum Expectation Value: 246.2 GeV
These big numbers might not mean anything to you, but Craig, speaking of the significance of these big “special numbers” and what would entail if these numbers were not so “special” and slightly altered, concludes:
“These are the fundamental constants and quantities of the universe. Scientists have come to the shocking realization that each of these numbers have been carefully dialed to an astonishingly precise value—a value that falls within an exceedingly narrow, life-permitting range. If any one of these numbers were altered by even a hair’s breadth, no physical, interactive life of any kind could exist anywhere. There’d be no stars, no life, no planets, no chemistry.”
With these extraordinarily huge and special numbers in mind, it seems crazy to think that that these numbers that describe the initial conditions of the Big Bang are necessary or “lucky.” Thus, the inference to the best explanation seems to be intelligent design.
And the best explanation of an intelligent designer of the universe is God.
For more on the Fine-Tuning Argument, click here.
#4- The Free-Thinking Argument
Here’s a newly-worded version of the syllogism I’ve made popular over the past few years. By the word “nature,” I am referring to the kinds of stuff that scientists can directly test or discover.
- If naturalism is true, then only nature exists (no souls, angels, demons, or God).
- If there is no “supernatural” aspect of humanity, then everything about humanity—including all thoughts and beliefs—would be causally determined by the forces and events of nature (i.e., physics and chemistry).
- If all things about humanity—including all thoughts and beliefs—are causally determined by the forces and events of nature, then it is impossible for humans to rationally infer best explanations (over false beliefs) and rationally affirm knowledge claims.
- It is possible for humans to infer best explanations (over false beliefs) and rationally affirm knowledge claims (it is self-defeating to offer knowledge claims against this premise).
- Therefore, not all things about humanity are causally determined by the forces and events of nature.
- Therefore, a supernatural aspect of humanity exists (like a “soul” or immaterial mind).
- Therefore, naturalism is false (souls or immaterial minds exist).
- Speaking of inference to the best explanation: the best explanation of the existence of a supernatural aspect of humanity is God (and the biblical view of God seems to make the most sense).
The first three steps of the argument are rather straightforward. In summary, (1) is true by definition: “If naturalism is true, nature is all that exists.” Premise (2) is tantamount to “If all that exists is nature, then everything about humanity is causally determined by the forces of nature, the initial conditions of the big bang, and perhaps some quantum events, all of which are outside of human control.” (3) expresses the fact that “If all things are causally determined, then that includes ALL thoughts, beliefs, evaluations, and judgements.”
If all of a person’s thoughts, beliefs, evaluations, and judgements are always forced upon her (and she had no opportunity to be more careful and choose better thoughts, beliefs, evaluations, or judgements) then she is simply left assuming that her determined thoughts, beliefs, evaluations, and judgements are good (and that her beliefs are true). Therefore, one could never rationally affirm that her beliefs really are the inference to the best explanation; this can only be assumed, and this assumption would likewise be causally determined and forced upon her.
A sense of vertigo is warranted!
This, then, is the paramount concern for the atheistic naturalist who affirms the exhaustive determinism of humanity. If determinism is true, then atheists—or anyone else for that matter—cannot possess justification for their belief in atheism or naturalism. And if justification is required for knowledge (which the majority of epistemologists affirm), then the atheist or naturalist cannot possess knowledge based upon justification either. It follows that if the naturalist “knows” that naturalism is true, then naturalism is false. It makes much more sense to conclude that naturalism is false, and that God and things like God (such as souls) exist.
Bottom line: if you believe that you are a rational free-thinker who is not ultimately “mind-controlled” by something else, then you should reject atheistic naturalism and affirm that both God and soul exist.
For more on the Free-Thinking Argument, click here.
#5- The Ontological Argument
There are several forms of the Ontological Argument, and they usually focus on the idea of the possible existence of a “maximally great being” (what many consider to be the definition of “God”). That is to say, is it “possible” that a maximally great being exists, or is there some illogical and incoherent notion about a being who exists necessarily and is omnipotent, omniscient, and omni-benevolent?
The argument usually looks something like this:
1- It is possible that God (a Maximally Great Being) exists.
2- If it is possible that God exists, then God exists in some possible worlds.
3- If God exists in some possible worlds, then God exists in all possible worlds.
4- If God exists in all possible worlds, then God exists in the actual world.
5- If God exists in the actual world, then God exists.
The Ontological Argument is logically valid and really comes down to the first premise (as the others follow from the rules of modal logic). So, even if an atheist doesn’t think that God probably exists, if one affirms that there is even the smallest of chances that they could be wrong – because the concept of God is logically possible – then, God exists.
Some think that this argument is too easy, or too good to be true. However, this argument only seems to work with the concept of a Maximally Great Being, as all parodies of this argument have been shown to fail (such as a “maximally great pizza”). That gets my attention and provides further reason to think that a Maximally Great Being (God) really does exist!
For more on the Ontological Argument, click here.
#6- The Leibnizian Cosmological Argument
Gottfried Wilhelm Leibniz was a German philosopher, mathematician, a metaphysician and an expert in logic who is recognized for his independent invention of the differential and integral calculus. He also crafted an argument for the existence of God that continues to be discussed today by leading philosophers in academia. Some refer to his case as “The Argument from Contingency,” but it is most commonly known as “The Leibnizian Cosmological Argument.” Consider the deep thoughts of Leibniz one step at a time:
1- Everything that exists has an explanation of its existence — either in the necessity of its own nature or in an external cause.
2- If the universe has an explanation of its existence, that explanation is God.
3- The universe exists.
4- Therefore, the explanation of the universe’s existence is God.
The fourth step of the argument is a deductive conclusion that follows logically if the three premises are true. Moreover, this also means that if the three premises are merely probably true, then one is completely rational in affirming the final conclusion. So, the question is raised: are the premises true or probably true?
Surely, no reasonable person will deny the third premise. What about the first premise? Is it true or probably true? We sure like to find explanations to all things. Indeed, it is the job of the scientist to find explanations. Moreover, it seems that anything and everything must have an explanation of its existence. It is either contingent upon something else, and if it’s not, then it must exist necessarily. With that said, the universe sure seems to be a contingent type of thing. Indeed, most scientists would affirm that the universe does not have to exist. After all, if Big Bang cosmology is true, then the universe has not always existed. And anything that has ever failed to exist, or could fail to exist, is necessarily not necessary.
Some committed atheists contend that while this is true of everything else, the universe is different. They go on to deny this first premise by saying things like, “the universe just exists without an explanation and there is no explanation needed!” But this commits what is known as the Taxi Cab fallacy. This logical error occurs when one hops in the “taxi-cab” (so-to-speak) and assumes a certain worldview attempting to make particular points but then jumps out of the system of thought when it goes against a certain presupposition they blindly support. This is not good reason to reject the premise.
So, it all comes down to the second premise. But why think that if the universe has an explanation of its existence, that this explanation must be God?
It is because the universe is everything nature, time, and space, including all nature, time, and space. This means that all nature is contingent upon something supernatural. All space is contingent upon something spaceless (and thus, immaterial, since matter requires space). All time is contingent upon something timeless (and thus eternal without beginning).
A supernatural, space-less, immaterial, time-less, eternal, and beginning-less (which also seems to exist by a necessity of its own nature) “Thing” in which the universe is contingent seems to be what we mean by “God.”
Therefore, God exists.
For more on the Leibnizian Cosmological Argument, click here.
So, which is my favorite?
If push comes to shove, I suppose I am partial to the FreeThinking Argument (I am fully aware of my bias). But, depending upon the person I am talking to (since we are all “wired” differently), sometimes one argument will have a stronger impact than others. Indeed, I have used each of these arguments to “close the deal” (as it were) when discussing the existence of God.
For example, if I am talking to a scientist, I will often offer the Kalam and provide the scientific support for each premise. If I am talking to a college student who is an atheist and a “woke anti-racist,” then I will provide the Moral Argument (see, If You Think Racism Is Wrong, You Should be a Christian). And if I am talking to a Christian who needs a little more support to strengthen their faith, I occasionally turn to the Ontological Argument.
I encourage all Christians to be familiar with at least one or two of these arguments for the existence of God and then always add the argument based on the historical evidence of Jesus’s Resurrection (Happy Easter) — which if God exists shows that Christianity, in particular, is true (click here for an example). So, choose wisely, and as usual . . .
Stay reasonable (Isaiah 1:18),
Dr. Tim Stratton
 This section is taken from the forthcoming Human Freedom, Divine Knowledge, and Mere Molinism Study Guide.