How Do We Know God Is One?
By Hamza Andreas Tzortzis
(Last updated 30 September 2015)
“Islam’s creative gift to mankind is monotheism, and we surely dare not throw this gift away.”
Islam is a way of life that has a simple yet profound theme permeating all aspects of its worldview. This theme is Oneness. In line with our reason and natural disposition, Islam teaches humanity to investigate and ponder on the harmony in nature and the entire cosmos. It concludes that harmony is the imprint of Divine Oneness on the created world. This idea of oneness doesn’t only refer to God’s creative acts, it also refers to Divine singularity. This relates to the fact that God is uniquely One, including the idea that He deserves our gratitude and love. Significantly, it refers to the fact that all acts of worship are to be singled out to Him alone. This essay will present a range of arguments to substantiate that God is uniquely one. A forthcoming essay will elaborate on why God deserves our worship, so elaborating on the worship aspects of Divine Oneness is not part of the scope of this essay.
The Oneness of the God, the creator, is not only an intuitive and natural belief, but a range of arguments proves it. These arguments include:
1. The Argument from Exclusion
2. Conceptual Differentiation
3. Occam’s Razor
4. The Argument from Definition
5. The Argument from Revelation
The Argument from Exclusion
God by definition has a will. If He never had a will it would imply that God did not create the universe by His own volition, and that there were an external set of factors or circumstances that made Him create. This contradicts the monotheistic conception of Divine independence and transcendence, hence all mainstream monotheist traditions postulate that God must have a will. The Qur’an affirms this fact too, it states that God “carries out whatever He wills.”
Putting theology aside, there are a number of reasons why God, the uncreated creator, must have a will. Firstly, since God, the creator, is eternal and brought into existence a finite universe, it must have chosen the universe to come into existence. Something that has a choice obviously has a will. Secondly, the universe has conscious beings that have a will and volition, therefore the one who created the universe with living beings that have a will, must also have a will. One cannot give something to a thing that it doesn’t already have. Therefore the creator has a will. However how many wills can there be? The argument of exclusion stipulates that there can only be one will, and therefore one creator.
Imagine there was more than one creator; for the sake of argument let’s say there were two. One of the creators, creator A wanted to move a rock, and the other creator, creator B, wanted also wanted to move the rock. There are three possible scenarios that can arise.
1. One of the creators overpowers the other by moving the rock in a different direction to the other.
2. They both cancel each other out, and the rock doesn’t move.
3. They both move the rock in the same direction.
The first scenario implies there is only one will that manifests itself. The second scenario means that there is no will in action. This is not possible because there must be a will acted upon as we have creation in existence. The third scenario ultimately describes only one will. Therefore, it is more rational to conclude that there is only one creator because there is only one will.
Now if one argues that you can have more than one entity and still have one will, I would respond by asking how do you know there is more than one entity? It sounds like an argument from ignorance because there is no evidence whatsoever for such a claim. This leads us to the next argument.
For two concepts or entities to exist, they must be different in some way. For example, if you have two trees, they will differ in size, shape, colour and age. Even if they had identical physical attributes there would be at least one thing that allows us to distinguish that they are in fact two trees. This can include their placement or position. You can also apply this to two twins; we know there are two twins because there is something that makes them different. This could even be their position and the mere fact they can’t occupy the same place at the same time.
If there were more than one creator, then there must be something to differentiate between them. However, if what they are the same in every possible aspect, then how can we say there are two?
If something is identical to another, then what is true of one is also true for the other. Say we had two things, A and B. If they are the same in every way, and there is nothing that allows us to differentiate between them, then they are the same thing. We can turn this into a hypothetical proposition “if whatever is true of A is true of B, then A is identical to B”.
Now let us apply this to the creator. Suppose we imagine that two creators exist, called creator X and creator Y, and that whatever is true of creator X is also true of creator Y. For instance, creator X is All-Powerful and All-Wise; so, creator Y is All-Powerful and All-Wise. How many creators are there in reality? Only one, due to the fact that there is nothing to differentiate between them. If someone were to argue that they are different, then they would not be describing another creator, but something that is created, as it would not have the same attributes befitting to the creator.
Since the one who claims that there may be two creators, whether a polytheist or sceptic, they would have to agree that whatever is true of creator X is true of creator Y, therefore God X and God Y are identical. This means creator X and creator Y are the same entity and not two different entities. If the polytheist or the sceptic still argues that there can be two creators and they are different from each other, then I would simply ask, ‘how are they different?’ If they attempt to answer the question, they enter the realm of arguing from ignorance, and therefore not arguing at all.
In light of the above, you may have the odd irrational folks who still posit a plurality of creators or causes all occurring at the same time. In light of Ockham’s Razor this is not a sound argument. Ockham’s Razor is a philosophical principle attributed to the 14th century logician and Franciscan friar William of Ockham. This principle enjoins, “Pluralitas non est ponenda sine necessitate”, in English “Plurality should not be posited without necessity.” In other words the simplest and most comprehensive explanation is the best explanation.
The key points of this principle entail that in absence of any evidence, or a need for a plurality of causes, we should hold onto the most comprehensive and simplest explanation. In this case we have no evidence to say the creator for the universe is actually a combination of two, three or even one thousand creators, so the simplest explanation is that the creator is one. Postulating a plurality of creators does not add to the comprehensiveness of the argument either. In other words to add more creators would not enhance the argument’s explanatory power or scope. For instance, to claim that an all-powerful creator created the universe is just as comprehensive as to claiming two all-powerful creators created it. One al-powerful creator is all that is required, simply because it is all-powerful. I would argue that postulating multiple creators actually has a reduced explanatory power and scope; this is because it raises far more problems than it solves. For example, the following questions expose the rational weakness of this form of polytheism; how do many external beings co-exist? What about the potential of any conflicting wills? How do they interact?
A popular contention to this argument is that if we were to apply this principle to the pyramids in Egypt we would absurdly adopt the view that it was made by one person, because it seems to be the simplest explanation. This is a misapplication of the principle, because the comprehensiveness part of the principle is ignored. Taking the view that the pyramids were built by one person is not the simplest and most comprehensive explanation, as it raises far more questions than it answers. For instance, how can one man build the pyramids? It is far more comprehensive to postulate that it was built by many men. In light of this, someone can say that the universe is so complex that it would be absurd to postulate that only one creator created it. This contention, although valid, is misplaced. A powerful being creating the whole universe is a far more coherent and simple explanation than a plurality of creators, because it raises the unanswerable questions raised in the previous paragraph. Nevertheless, the critic may continue to argue that it wasn’t one person that created the Pyramids, but it was an all-powerful creator. The problem with this is that nothing within the universe is an all-powerful being, and since the Pyramids are buildings, and buildings are built by an efficient cause (a person or persons that act), then it follows the Pyramids must have been created of the same type of cause. This leads us back to the original point, that there must have been more than one of these causes required to build the Pyramids.
The Argument from Definition
Reason necessitates that if there were more than one creator who created the universe it would be in chaos. There would also not be the level of order we find in the cosmos. The Qur’an has a similar argument,
“Had there been within the heavens and earth gods besides God, they both would have been ruined.”
The classical commentary known as Tafsir Al-Jalalayn states that “heaven and the earth would have lost their normal orderedness since there would have inevitably been internal discord, as is normal when there are several rulers: they oppose one another in things and do not agree with one another”.
However one may point out that since more than one person made your car; one person fitted the wheels, and someone else installed the engine and another person installed the computer system, then maybe the universe was created in the same way. This example indicates that a particular thing can be created with more than one creator.
In order to respond to this contention what has to be understood is that the best explanation for the origins of the universe is the concept of God and not just a ‘creator’ (to be explained in a forthcoming essay). There may be an abstract conceptual possibility of multiple creators, as highlighted by the car example, but there cannot be more than one God. This is because God by definition is the being that has an imposing will that cannot be limited by anything external to Him. If there were two or more Gods that would mean that they would have a competition of wills and that would result in chaos and disorder. The universe we observe is governed by mathematical laws and order, therefore it is the result of one imposing will. Interestingly, the objection above actually supports monotheism. In order for the car to work the different people who were responsible for making it had to conform to the overall “will” of the design. This shows that things external to them limited their wills. Since God, by definition, cannot have His will limited by anything outside of Himself, it follows that there cannot be more than one Divine will.
However one may argue that multiple Gods can agree to have the same will or they can each have their own domain. This would mean that their wills are now limited and passive, which would mean they are not Gods anymore by definition!
The 12th century Muslim thinker and philosopher Ibn Rushd, also known as Averroes in the western tradition, summarises this argument,
“The meaning of the…verse is implanted in the instincts [of man] by nature. It is self-evident that if there are two kings, the actions of each one being the same as those of the other, it would not be possible [for them] to manage the same city, for there cannot result from two agents of the same kind one and the same action. It follows necessarily that if they acted together, the city would be ruined, unless one of them acted while the other remained inactive; and this is incompatible with the attribute of Divinity. When two actions of the same kind converge on one substratum, that substratum is corrupted necessarily.”
The Argument from Revelation
A simpler way of providing evidence for God’s oneness is to refer to revelation. This argument postulates that if God has announced himself to humanity, and this revelation can be proven to be from Him, then what He mentions about Himself is obviously true. However, a sceptic may question some of the assumptions behind this argument; that God has announced Himself to mankind and that the revelation is in the form of a book.
Let’s take the last assumption first. If God has announced himself to mankind there are only two possible ways to find out: externally and internally. What I mean by “internally” here is that you can find out who God is solely by introspection and internalisation and what I mean by “externally” is that you can find out who God is via communication outside of yourself, in other words it is instantiated in the mind-independent world. Finding out about God internally is implausible for the following reasons,
1. Human beings are different. They have, what Psychologists call, “individual differences”, these individual differences include DNA, experiences, social context, intellectual and emotional capacities, gender differences, amongst many more. These differences play a role in your ability to internalise via introspection or intuition, therefore the results of introspection or relying on your intuition will differ. So you can see that if these processes where solely used to find out about God there would be inevitable differences in our conception of Him. This is true from a historical point of view, since the ancient world 6000 BCE, there are records of approximately 3,700 different names and concepts for God.
2. Since the method used to conclude that God does exist is a “common sense” method, or what philosophers call rational thought and what Muslim theologians may call innate thinking, then internally trying to find out about God would lead to fallacies. Using the cosmos as evidence we can conclude that there is a creator. This creator must be transcendent, independent, eternal, unique, powerful, knowing and has a will; anything else would be speculation. There may be a few more attributes that we can derive from pondering on creation, but understanding the Divine as the way He wants us to understand Him requires revelation. The Qur’an aptly rebukes mankind by warning us not to say about God of that which we have no knowledge. Trying to internalise what God is would be equivalent of a mouse trying to conceptualise and think like an Elephant. It is obvious that the human being is not eternal, unique and powerful, therefore the human being could not accurately conceptualise who God is. God would have to tell you via external revelation.
Take the following example into consideration, you know God exists like the knocking of the door, you safely assume that something is there, but do you know who it is? You weren’t expecting anyone, so you cry out “who is it?” in order to find out, and the only way to find out is if the person behind the door tells you. So you can conclude that if God has said or announced anything it must be external to the human being.
From an Islamic perspective this external communication is the Qur’an as it is the only text to claim to have come from God that fits the criteria for a divine text, these criteria include,
i. It must be consistent with the rational and intuitive conclusion on God. For example if a book says God is an Elephant with 40 arms you could safely assume that this book is not from God, as God must be external to the universe and independent. An Elephant, regardless of form, is a dependent being. This is because it has limited physical qualities such a size, shape and colour. All things with limited physical qualities are dependent because there are external factors that dictate their limitations. Therefore anything with limited physical qualities cannot be God, as God is not “physical” and is independent.
ii. It must be internally and externally consistence. In other words if it says on page 20 that God is one and then on page 340 its says God is 3 that would be an internal inconsistency. Additionally if the book says that the universe is only 6,000 years old then that would be an external inconsistency as reality as we know it affirms that the universe is older than that.
iii. It must have signposts to transcendence. In simple terms it must have evidence to show that it is from God.
The Qur’an – and this essay is not the place to discuss this in any depth – cannot be explained naturalistically therefore supernatural explanations are the best explanation. Some of these signposts include:
i. The Qur’an’s linguistic and literary inimitability.
ii. There are historical accounts in the Qur’an that could not have been known by man at the time of revelation.
iii. Its unique arrangement and structure.
To conclude, since the only way to know what God has announced to mankind is via external revelation, and this revelation can be proven to be the Qur’an – then what it says about God is true. The Qur’an states, “Say, ‘He is God, the uniquely One.'” Therefore using the argument above, it necessarily follows that God is indeed One.
These are some of the arguments that can be used to show that God is one; however this topic – once truly understood – will have some profound effects on the human conscious. The oneness of God is not only related to the fact that He is uniquely one, rather it refers to His worship, lordship, names and attributes, something that can only be tasted by pondering on reality, meditating on the meaning of the Qur’an, and becoming a manifestation of its message.
 The Qur’an, Chapter 11, Verse 107
 The Qur’an, Chapter 21, Verse 22
 Tafsir Al-Jalalayn. Translated by Aisha Bewley. Dar-Al Taqwa. 2007, p. 690.
 Averroes. Faith and Reason in Islam: Averroes’ Exposition of Religious Arguments. Translated by Ibrahim Najjar. One World. 2001, p. 40.
 The Qur’an, Chapter 10, Verse 68
 This is obviously coherent from the ashari and maturdi conceptions of the Islamic creed. However some may contend this is not so for the athari creed. The athari creed argues that although God’s descriptions of Himself is to be understood via His transcendence and uniqueness, the descriptions themselves are to be taken literally but without establishing a modality (or howness; kayfiyyah كَيْفِيَّة). Therefore, one may misconstrue God’s “hands” as being limited, because hands are limited by definition. From an athari point of view this is incorrect, it does not specify a howness or what it implies for God to have “hands”, it just affirms what the Qur’an mentions without discussing the modality, while at the same time affirming the transcendence, independence and uniqueness of God. The athari creed negates any material physicality to God, and affirms His transcendence. I wanted to add this note to show that this argument is credal neutral.
 Read the essay “God’s Testimony” here https://iera.org/research/essays-articles/gods-testimony-inimitability-divine-authorship-quran.
 For more on the Divine nature of the Qur’an please read the book The Eternal Challenge: A Journey Through The Miraculous Qur’an by Abu Zakariya. One Reason Publications. 2015. See also “Ring Theory: The Qur’an’s Structural Coherence” http://www.islam21c.com/islamic-thought/ring-theory-the-qurans-structural-coherence/.
 The Qur’an, Chapter 112, Verse 1