In the name of Allah, the gracious, the merciful.
All praise and gratitude is due to Allah, the Lord of everything that exists. May his peace and blessings be upon His final Prophet and Messenger, Muhammad ﷺ.
PRELUDE
The Kalam Cosmological Argument stands as one of the most enduring and intellectually resilient arguments for the existence of God. Rooted in Islamic theological thought, its earliest systematic formulation is often attributed to the great Muslim polymath Imam Abu Hamid al-Ghazali (d. 1111), who in his seminal work Tahāfut al-Falāsifa (The Incoherence of the Philosophers) sought to defend the rationality of belief in a created universe with a temporal beginning. For al-Ghazali, the world was not eternal but brought into existence by a willful, necessary being—God. His philosophical critique of Greek-influenced metaphysics laid the groundwork for what would later become a formal cosmological argument grounded in both logic and theology.
In the modern Western philosophical world, Dr. William Lane Craig emerged as the most prominent voice in reviving and defending the Kalam argument. His contribution has been nothing short of monumental. Through rigorous academic work and numerous public debates, Craig has equipped the argument with a robust metaphysical and scientific foundation—drawing from Big Bang cosmology, thermodynamics, and modern philosophical reasoning. He has skillfully developed a range of pre-emptive and responsive rebuttals to withstand the critiques of both classical skeptics and contemporary New Atheists, thereby securing the argument’s place in modern apologetics.
However, this paper invites a deeper reflection—one that respectfully questions the theological trajectory of Craig’s application of the Kalam. While the argument convincingly leads to the existence of a cause that is timeless, spaceless, immaterial, and personal, it does not naturally extend to support the doctrine of the Trinity. Rather, as will be shown, the Kalam, in its purest philosophical form, points compellingly toward a singular, indivisible, and absolute monotheism—strikingly closer to the Islamic conception of God than to the complex triune model proposed in Christian theology.
The purpose of this paper, therefore, is not to challenge the validity of the Kalam itself, nor to diminish the scholarly excellence of Dr. Craig’s contributions. On the contrary, it seeks to affirm the argument’s philosophical strength while highlighting a crucial limitation: the Kalam Cosmological Argument, as constructed and defended, cannot reasonably be used to justify belief in a triune God. Through philosophical analysis and theological reflection, this article aims to demonstrate that the argument—despite being employed within Christian apologetics—inevitably supports pure monotheism.
ARTICLE
– Introduction
To properly understand why the Kalam Cosmological Argument does not support the Christian concept of God, we must begin with two key ideas. First, we need to understand what the Kalam argument actually is and what it seeks to prove. Second, we must look at how Christianity defines God, particularly through the doctrine of the Trinity. Once these two ideas are clearly laid out, we will be in a better position to explore whether it is reasonable or logically consistent to use the Kalam argument as a foundation for Trinitarian belief
– The Argument and what it seeks to prove
The Kalam Cosmological Argument seeks to prove the existence of God. It is a deductive argument that reflects syllogistic reasoning; therefore, if its first two premises are true, the conclusion necessarily follows with logical certainty. The argument goes as follows:
P1: Whatever begins to exist has a cause
P2: The universe began to exist
C1: Therefore, the universe has a cause
Based on these premises, Prof. Craig seeks to establish a cause for the universe. He then moves on to explain what kind of cause this would be—such as transcendent (as it is beyond time) and immaterial (as it is beyond matter) (1) . Based on these and other explanations, he concludes that this cause is none other than the God of the Bible. However, he misses out on an important detail—arguably the most important of them all.
Chronologically, as mentioned in the Prelude, this argument was primarily stated by al-Ghazali and was later adopted by Prof. Craig (2) . Hence, similar to any theologian or philosopher, when al-Ghazali originated this argument, he had in mind the aim of proving monotheism(3) . In fact, one does not have to be a philosopher to realize that when making an argument, the objective is to prove one’s own point. Prof. Craig, however, missed out on this crucial detail. When he took al-Ghazali’s argument, he failed to acknowledge that, although both he and al-Ghazali were theists, they did not accept each other’s model of theism. Hence, this argument required alteration— something Prof. Craig did not undertake.
Now, that leaves his argument with a fundamental flaw. That is, it now presupposes that an argument seeking to prove monotheism can also be used to justify the trinity. This concern can be expressed more formally in the following structure:
P1: Al-Ghazali developed the Kalam argument to defend pure, indivisible monotheism.
P2: William Lane Craig adopts the Kalam to defend the Christian doctrine of the Trinity. P3: The Islamic and Christian conceptions of God are fundamentally different.
P2: The Islamic and Christian conceptions of God are fundamentally different.
P4: Therefore, using the Kalam without theological adaptation leads to inconsistency.
C1: The Kalam argument, as it stands, cannot consistently support Trinitarian theology.
While Prof. Craig has answered almost all objections regarding God and the Kalam argument, he still hasn’t addressed this flaw with sound reasoning. It is as if he hasn’t realised that the God of the Bible is fundamentally different from the God of other Abrahamic faiths. Although I haven’t started my series of arguments yet, one might stop right here and think:
“Even if al-Ghazali intended to prove Islamic monotheism, that doesn’t mean the argument itself can’t be neutral or adaptable to other theistic views.”
If you are amongst them, consider this: the logical structure of the Kalam—particularly the kind of cause it leads to—is far more compatible with a singular, indivisible God (as we will see). The idea of a triune being adds complexity that is neither demanded nor supported by the premises of the argument. That’s the reason why I have mentioned in my argument’s fourth premise (P4, page. 6) that if the Kalam is to be adopted by Christians, it requires alteration.
– The God of the Christians
Understanding the Kalam argument alone is not enough; to fully assess its application in Christian theology, we must also explore the Christian concept of God. Broadly speaking, Christians hold to the doctrine of the Trinity, but within this belief, two major interpretive models have developed:
The One-Self Model (also called the Latin or Western model)
This model holds that God is one being with one self or one center of consciousness, yet this one self exists in three distinct modes or relations: the Father, the Son, and the Holy Spirit. These are not separate persons in the modern psychological sense but are rather understood as relational distinctions within the single divine self. Critics however argue this model leans toward modalism, a view rejected by mainstream Christianity as heretical.
The Three-Self Model (also called the Social or Eastern model)
In this view, there are three distinct persons—Father, Son, and Holy Spirit—each with a distinct center of consciousness and will, yet all sharing the same divine essence.
– Prof. Craig’s Model and our approach
Amongst the above mentioned models of Cristian theism, Prof. Craig tends to lean towards the “Three-self model” which is quite evident from his writings:
“My suggestion is that we think of God as a soul endowed with three sets of rational faculties, each sufficient for personhood, so that God is tri-personal.” (4)
“I very deliberately take what is called a “social Trinitarian view, ” according to which God has three centers of self-consciousness called Father, Son, and Holy Spirit in eternal communion with one another. ” (5)
Hence with the One Self-Model being termed as heretical and Prof. Craig following the Three-Self Model, moving forward, our focus would be on the Kalam and the Three Self-model.
– How the Kalam Undermines the Trinity
Following are the arguments demonstrating how the Kalam argument does not support Christian theism.
First argument – Singularity of the necessary existence. Philosophically speaking, all of existence can be classified into two fundamental categories:
- Necessary existence: A being whose non-existence is impossible. It exists by its own nature, is uncaused, and is entirely independent. Everything else depends upon it.
- Contingent existence: A being that does not have to exist. It depends on something else for its existence and could have failed to exist.
William Lane Craig, while defending the Kalam argument, affirms this distinction when he states: “This cause must be itself uncaused because we’ve seen that an infinite series of causes is impossible.” (5)
The rejection of an infinite regress of causes leads us logically to the necessity of a first, uncaused cause—one that stands at the base of all contingent reality. However, it is essential to understand that this regress must terminate, not at multiple uncaused causes, but at a single necessary existence. Here’s why:
If contingent beings exist (and we know they do), and infinite regress is not possible (as Prof. Craig affirms), then the only logical alternative is that all contingent beings ultimately trace back to a single, self-sufficient source—a being that does not rely on anything else.
Therefore, the conclusion is firm: only one being can be necessary. Any plurality within the necessary would entail composition or dependence, undermining its status as necessary.
Now, if we turn to Christian theology—especially the Trinitarian model—it introduces the Father, Son, and Holy Spirit as co-equal and co-eternal persons. However, under the light of the Kalam and the principle of necessity, a serious issue arises: If the Son is not the Necessary Existence, then He depends on something else for His existence—and thus cannot be fully God in the same way the Father is claimed to be.
And if He is necessary alongside the Father, we’re faced again with multiple necessary beings, which collapses under the philosophical pressure we just laid out.
At this point an idea of Shared Causality is used by the christians where they make the following objection :
“Just as both a mother and father are necessary for the birth of a child, the Father and Son are both necessary causes of the universe”
While intuitively appealing, this analogy breaks down under philosophical scrutiny. Here’s why:
This line of reasoning implies inter-dependence. In human reproduction, neither the father nor the mother alone is sufficient—each depends on the other for the act of creation. If this model is applied to the divine persons, it logically leads to the conclusion that the Father and the Son depend on each other to bring the universe into existence.
But such mutual dependence violates the very definition of a necessary being, which is “a being free from dependency.”
To be necessary, a being must possess absolute ontological independence. It cannot be partially dependent on another, even if that other is said to be divine. Dependency—of any kind—immediately renders the being contingent or at least composite, and therefore not self-sufficient or necessary.
Hence, the analogy collapses. The Kalam demands a singular, noncomposite, independent cause. And that cause, by necessity, must be One—undivided, absolute, and truly necessary.
Second argument – The Temporal Dilemma of the Son’s Eternal Generation
Moving on, we now turn our focus to the Christian belief that the Son is “eternally begotten” of the Father. While this idea might seem theologically sound within Christian doctrine, it begins to unravel when examined through the lens of the Kalam Cosmological Argument, especially as defended by Professor William Lane Craig. What at first seems like a coherent theological belief runs into serious problems when measured against the philosophical foundations that support the Kalam. The doctrine of the Son’s eternal generation creates not only a theological issue but also a logical contradiction between time, causality, and the very nature of necessary existence—a contradiction that challenges the use of the Kalam to defend the Trinity.
The Kalam Cosmological Argument is built on a key premise: “Whatever begins to exist has a cause.” To defend this, Craig supports the A-theory of time, also called the tensed theory of time. According to this view, time flows in a real way: the past is gone, the future hasn’t happened yet, and only the present is real. Craig firmly rejects the B-theory of time, which treats all moments—past, present, and future—as equally real and unchanging. His rejection of this view is not a minor point; it is central to his argument that the universe must have had a real beginning, and that it cannot be the result of an infinite chain of causes. Based on this understanding, Craig argues that the universe had a start, and therefore it must have a first uncaused cause—something that exists before and beyond time itself.
Now compare this with the Christian doctrine of the eternal generation of the Son. This teaching says that the Father eternally begets the Son, and the Son is eternally begotten—not as a creation in time, but as a timeless relation within the divine being. This is not meant to suggest that the Son was created or is inferior, but rather that there is a real, eternal relationship between Father and Son. However, this is where the contradiction begins. If the begetting of the Son is a real act and not just a metaphor, then under Craig’s A-theory of time, it must either happen in time, or it cannot happen at all. If it happens in time, then the Son had a beginning—which goes against Christian teaching that the Son is eternal. But if the begetting happens outside of time—timelessly—then that conflicts with Craig’s rejection of timeless events and his insistence that real events require temporal becoming.
This creates a deeper philosophical issue. If the Father’s begetting of the Son is eternal and real, then it implies a causal relationship that has no beginning and no external cause. But this leads to an infinite causal chain within the Godhead—exactly the kind of infinite regress that Craig argues is impossible. If an infinite past of physical causes is not possible, then why should an infinite internal divine causality be acceptable? It is inconsistent to reject an infinite series in the universe while accepting one within the nature of God. The same logic that Craig uses to argue for a first cause of the universe ends up contradicting the very idea of an eternally begotten Son.
Even more significantly, the Kalam points to a being that is necessary, uncaused, and completely independent. This being must exist by its own nature and depend on nothing else. Yet, according to Christian theology, the Son depends on the Father for His existence. He is begotten—not created—but still derived. This means the Son is not aseitic (self-existent), but instead relationally dependent. And anything that is dependent cannot be the necessary being that the Kalam aims to establish. If the Son is not necessary, then He cannot be fully divine in the metaphysical sense. If only the Father is necessary and uncaused, then Christian theism turns into a hierarchical theism, not a co-equal Trinity.
So, we are left with a serious conclusion. The Son, by being begotten, is dependent. If He is dependent, then He is not necessary. If He is not necessary, then He cannot be the first cause of the universe. And if He is not the first cause, then the Kalam Cosmological Argument cannot support Trinitarian theology.
The structure of the Kalam leads us to a very different picture of God. It points to one being who is uncaused, independent, indivisible, and necessary. A being with no internal divisions, no temporal sequence, and no dependency. That is the image of pure monotheism—not a God who exists as three co-equal persons. While the Kalam is powerful in defending the idea of a Creator against atheism, it simply does not fit with the theological commitments of the Trinity. Any attempt to force it into that framework leads to contradictions too great to ignore.
References
[ 1 ] – The Kalam Cosmological Argument, Reasonable Faith
[ 2 ] – The kalam Cosmological Argument (book), pg 42
[ 3 ] – Incoherence of the Philosophers, 5th Discussion, pg 84. Gazali wrote an entire chapter to disprove multiplicity of God, hence its evident that he had, in his mind, the idea of proving monotheism.
[ 4 ] – #479 What Does it Mean to Say God Is a Soul?, Reasonable Faith
[ 5 ] – #705 Is the Doctrine of the Trinity Kid Stuff?, Reasonable Faith
