Why Atheism Cannot Be True
(1) Introduction
The Argument from Rational Certainty is a transcendental argument for the existence of God. It begins with a basic observation — not about the physical world, but about our rational experience: we possess rational certainty. (Proviso -- I know some people deny that we possess rational certainty... but I would recommend anyone attempt to deny rational certainty next time you review your payslip or go to the bank to pay your bills. Denying rational certainty is like denying reality!)
From that single fact, it shows that such certainty requires an all-knowing mind to ground it. How so, I hear you say? If there is no all knowing mind, one that has defined what is objectively true and what is objectively false, then we cannot have certainty that anything at all is true or false. You are not convinced?
Stay with the me..
My contention is simply this: Any worldview that denies the existence of such a mind, including atheism, collapses into contradiction.
The argument is structured as follows:
- In part one I will introduce the argument and provides a brief overview.
- In part 2 I will provide a detailed justification for each premise.
- In part 3 I will summarise each justification and conclude!
This argument is structured deductively. If each premise is true, the conclusion follows necessarily. The argument is as follows:
- Premise 1: Rational certainty exists.
- Premise 2: Rational certainty requires a necessary precondition: an all-knowing mind.
- Premise 3: Any worldview that denies this necessary precondition cannot account for rational certainty without contradiction.
- Premise 4: Atheism is a worldview that denies the existence of such a mind.
- Premise 5: Therefore, atheism entails a contradiction: it depends on rational certainty while denying the precondition that makes rational certainty possible.
- Premise 6: A worldview that entails contradiction cannot be true.
- Conclusion: Therefore, atheism cannot be true and is necessarily false.
(2) Justifications
PREMISE 1: Rational Certainty exists:
To begin, we must define what we mean by rational certainty. Rational certainty is not the mere feeling of confidence or strong belief. It is the ontological possession of knowledge that cannot be mistaken. Notice here I am not just talking about any kind of “knowledge.” I am talking about knowledge that must be true and cannot be wrong.
Rational certainty is when someone knows something in such a way that the possibility of being wrong is excluded. We might encounter rational certainty in truths like mathematics and logic. For example, that 2 plus 2 equals 4, or that a thing cannot be both itself and not itself at the same time and in the same respect. Another example is the statement “I exist.” To deny your own existence requires your existence in order to make the denial.
==>> These are truths we appear to know with rational certainty. They cannot be false. <<==
Now consider someone who tries to deny that rational certainty exists. That denial faces the exact same problem as denying truth itself. If someone says “truth does not exist,” they are making a truth claim in the very act of denial.
==>> They are saying it is true that truth does not exist, which is a contradiction. <<==
Likewise, the person who says “rational certainty does not exist” is attempting to make a claim that would have to be supported by rational certainty in order to be meaningful. If they are not rationally certain of the claim “rational certainty does not exist,” then it is just an arbitrary assertion with no epistemic weight.
==>> But if they are rationally certain of their denial of rational certainty, then they have contradicted themselves. <<==
In other words, to meaningfully deny rational certainty is to presuppose it. Without rational certainty, there is no justification for the claim. You are simply expressing a belief, not demonstrating anything. So the only way to argue that rational certainty does not exist is to use rational certainty to do it. This is contradictory.
Therefore, rational certainty is inescapable. It exists in the same way that truth exists: as a necessary precondition for thought, reasoning, and argument.
==>> To deny it is to assume it. <<==
PREMISE 2: Rational Certainty requires a necessary precondition: An all-knowing mind to ground universal & necessary truths
Before we defend this premise directly, it is important to explain the kind of reasoning being used here. This is transcendental reasoning, which is not the same as circular reasoning. Circular reasoning occurs when someone assumes the very thing they are trying to prove, without providing any external justification. It is reasoning in a circle claiming “X is true because X is true” — which offers no independent grounds for said belief.
But transcendental reasoning is different. It asks a deeper question: What must be true in order for something else to be possible or actual? It does not assume the conclusion. Instead, it explores possible worlds and looks at which conditions must exist in order for certain features of reality exist or be true.
For example, if electricity cannot exist unless electrons exist, then in any possible world where electrons do not exist, electricity would not be possible. In other words: electrons are a necessary precondition for the possibility of electricity. If you imagine a world without electrons, it logically follows that there could be no electricity in that world.
Or take the case of rationality. Rationality is something that minds do. If you imagine a possible world in which no minds exist, then rationality could not exist in that world either. Therefore, minds are a necessary precondition for the possibility of rationality. And from that, it follows that if rationality exists, then minds must necessarily exist.
So notice: this is not circular reasoning. It is just recognizing that different kinds of possible worlds produce different kinds of outcomes, depending on what conditions are initially present.
==>> A world without minds cannot give rise to rational thought, just like a world without electrons cannot give rise to electricity. <<==
However, just because one thing is necessary for another to exist, that does not mean it is the only necessary thing. In many cases, multiple preconditions must be in place for something else to be possible.
For example, in order for electricity to exist in any world, that world must contain electrons. But that is not enough on its own. The world must also contain space, because electrons must have the ability to move. If a world contained no spatial dimension at all, then electrons could not move, and electricity could not occur. So there are at least two necessary preconditions for electricity to exist: electrons and space. In the same way, there are at least two necessary preconditions for rational certainty to exist. The first is that there must be at least one mind, and the second is that there must be an all-knowing mind.
> And that brings us to the core justification of this premise…
To possess rational certainty is to know something in such a way that it cannot be false. It is to hold a belief that is not just subjectively convincing, but objectively immune to error. However, for any finite mind, that kind of certainty is impossible to guarantee, because a finite mind does not have access to all truth. Because a finite mind is finite, that mind’s knowledge will always, necessarily, be limited, and that limitation creates the constant possibility that something unknown could overturn what it currently believes.
For example, imagine a person who is absolutely convinced that 2 plus 2 equals 4. On the surface, this appears to be rational certainty. But suppose they have lived their entire life in a controlled environment where everyone around them is part of an elaborate deception. All their teachers and materials have reinforced this claim as part of a long-running prank. Because they lack full knowledge of their situation, they are unaware that their certainty is based on a falsehood.
... I know this sounds crazy but bear with me for a moment ...
Or imagine someone who confidently believes they have constructed a sound logical argument. However, their reasoning contains a subtle but critical flaw that they are unable to detect. Perhaps they misunderstand a key term or overlook an invalid inference. Because they do not have access to the full range of facts or sufficient logical training, they are unaware of the error. Their mind gives them the sense of certainty, but that certainty is misplaced because it rests on faulty reasoning they cannot perceive.
Or consider the classic Matrix-style scenario. A person believes they have a family, a job, and a personal history. But in reality, they are a brain in a vat receiving electrical signals that simulate those experiences. Because they do not know what they do not know, their sense of certainty is misplaced.
In all of these cases, the common factor is that the individual is not all-knowing.
Because they lack complete knowledge, they are unable to eliminate the possibility that their belief is false. This is what we call rational UN-certainty.
Rational uncertainty is the condition of not possessing rational certainty. It is the state in which a mind holds a belief that feels justified, but which could still be false, because it cannot rule out the possibility of unknown information that would overturn it. A finite mind, by definition, is not aware of all that is real. There are always facts or realities it does not know. And because it does not know what it does not know, it is always exposed to possible defeaters — that is, unknown truths that could prove its current beliefs wrong.
Therefore, if all minds are finite, then all minds are necessarily rationally uncertain. No finite mind can ever rule out the possibility that it is wrong, because no finite mind is all-knowing. There is always the chance that something outside of its awareness could overturn what it believes to be true. In a world where only finite minds exist, rational certainty would be impossible. The only thing that would be possible is rational UNcertainty.
This means that the only way rational certainty can exist is, if at least one mind exists that knows all things and cannot be mistaken. Such a mind would not be vulnerable to being overturned by unknown facts, because there would be no unknown facts to this mind. It would have exhaustive access to everything in reality. This means it would be rationally certain by nature.
Moreover, such a mind could serve as the foundation for rational certainty in finite minds (like ours). Through revelation or some other form of communication, an all-knowing mind could impart truth in a way that secures rational certainty within finite minds. This means a finite mind does not need to become omniscient to have rational certainty; it only needs to receive truth from a source that cannot be wrong!
==>> Therefore, in order for rational certainty to be possible, the existence of an all-knowing mind is necessary. <<==
PREMISE 3: Any worldview that denies this necessary precondition (an all-knowing mind) cannot account for rational certainty without accepting a contradiction!
At this point in the argument, we have already established that rational certainty exists, and that in order for it to be possible in any world, that world must contain an all-knowing mind. Rational certainty, by its very nature, requires access to all truth, which only an omniscient mind could possess. Finite minds, no matter how confident they may feel, can only possess rational uncertainty (unless given rational certainty by an all knowing mind).
Now consider the kind of worldview that denies the existence of such a mind. Any worldview that does not include an all-knowing mind as part of its metaphysical structure is, by definition, a worldview in which only finite minds exist. But we have shown that finite minds alone cannot produce rational certainty. Therefore, any worldview that rejects the existence of an all-knowing mind eliminates the very condition that makes rational certainty possible.
To illustrate this, return to the analogy we’ve already used. In order for electricity to be possible, a world must contain electrons. But it must also contain space. Without space, electrons cannot move, and electricity cannot occur. So if a worldview claimed that electricity exists, but also claimed that space does not exist, that would be a metaphysical contradiction.
==>> It would affirm a consequence while denying a necessary precondition. <<==
The same is true here. If rational certainty is only possible in a world where an all-knowing mind exists, then any worldview that affirms rational certainty while denying such a mind is incoherent. It is affirming a consequence while denying the very thing that makes that consequence possible. That is a contradiction.
Contradictions are necessarily false, because they assert what cannot logically or metaphysically coexist. A worldview that affirms what it also denies is not merely incomplete. It is broken at its core.
Therefore, any worldview that denies the existence of an all-knowing mind must be false. It is logically and metaphysically self-defeating. Just as it would be contradictory to say “electricity exists in a world with no space,” it is contradictory to say “rational certainty exists in a world with no all-knowing mind.”
==>> It cannot be the case. Rational certainty is only possible in a world where an all-knowing mind exists. <<==
PREMISE 4: Atheism is a worldview that denies the existence of such a mind!
Having now established that rational certainty requires the existence of an all-knowing mind, we must ask: does atheism allow for such a mind to exist?
The answer is no. Atheism, by definition, is the belief that there is no God. It asserts that there is no transcendent, necessary, all-knowing mind who created and sustains the universe. In most cases, atheism is coupled with metaphysical naturalism, which is the view that reality is exhausted by physical processes and material causes. Minds, on this view, are the products of biological evolution—temporary configurations of matter that emerge within complex brains.
But if that is the case, then every mind in existence under atheism is finite, contingent, and fallible. No mind in that framework has access to all truth. No mind can know everything or guarantee the truth of its beliefs without the possibility of error.
==>> In short, atheism entails a world in which all minds are finite and limited. <<==
Now, if an atheist were to say that they believe an all-knowing mind does exist, they would, in effect, be conceding the existence of God while simply refusing to use the word. To affirm that there is a mind that knows all things, that cannot be wrong, and that exists necessarily outside of the limitations of space, time, and finitude, is to describe what all classical theists mean by “God.” To say that such a mind exists, but that it is “not God,” is absurd.
==>> If a being has the essential attributes of God, then that being is God. The label does not change the reality. <<==
So the atheist cannot grant that an all-knowing mind exists without abandoning atheism. They must deny that such a mind exists at all. And in doing so, they remove the very foundation that makes rational certainty possible. Atheists may attempt to avoid this implication by redefining God or by appealing to abstract entities like logic or mathematics as eternal, impersonal truths. But none of these alternatives provide the personal, all-knowing mind that rational certainty requires. Laws of logic cannot think, reason, or reveal truth. They are not minds. And abstract impersonal realities cannot serve as the ground for rational knowledge in personal minds.
Therefore, atheism directly entails the denial of the very precondition that rational certainty depends on. It is not just that atheism fails to include God as a possibility.
==>> It rules out the existence of the only kind of being that could ground rational certainty in the first place. <<==
PREMISE 5: Therefore, atheism entails a contradiction: it depends on rational certainty while denying the precondition that makes rational certainty possible!
At this stage of the argument, we have established that rational certainty exists, that it requires an all-knowing mind in order to be possible, and that atheism denies the existence of such a mind. What follows from these premises is that atheism is internally contradictory.
==>> It makes use of rational certainty while denying the necessary foundation that makes rational certainty possible. <<==
This leads to what is known as radical skepticism. Radical skepticism is the position that no one can have knowledge or certainty about anything. It is the view that all beliefs are ultimately unjustified, that truth is inaccessible, and that we cannot trust even our most basic reasoning faculties. Atheism, by denying the existence of an all-knowing mind, leaves us with nothing but finite minds. Minds that are necessarily subject to rational uncertainty. Without a perfect mind to ground truth, all knowledge becomes tentative, and the result is radical skepticism.
But as we have already shown in premise one, radical skepticism is false. The denial of rational certainty is self-defeating. To claim that we cannot be rationally certain of anything is to express rational certainty about our lack of it. This is a contradiction.
==>> At least one rational certainty must exist, or else the claim “there is no rational certainty” would collapse under its own weight. <<==
Therefore, rational certainty is transcendentally true. It cannot be denied without being affirmed. This creates a contradiction within atheism. If atheism is true, then there is no all-knowing mind, and therefore rational certainty is impossible. But rational certainty exists. The atheist is therefore left claiming both that rational certainty does and does not exist. That is a contradiction.
PREMISE 6: A worldview that entails contradiction cannot be true
This premise is one of the most basic principles in all of logic, reason, and metaphysics. It is known as the law of non-contradiction, and it states that a proposition cannot be both true and false at the same time and in the same respect. If a belief system or worldview leads to a contradiction, if it requires affirming that something both is and is not, then it must be rejected as false.
This is not a rule we arbitrarily impose. It is a law that makes reason itself possible. If contradictions could be true, then nothing could be trusted. Logic would collapse. Disagreement would be meaningless. Argument and evidence would have no purpose.
==>> A worldview that affirms contradiction cannot distinguish between truth and falsehood, because it treats them as the same thing. <<==
Contradiction is not just an imperfection. It is a logical impossibility. It is to affirm that what is false is true, and what is true is false, simultaneously. And any worldview that leads to such a result refutes itself. It cannot be accepted, no matter how appealing its conclusions might seem, because it undermines the very foundation of truth.
In the previous premise, we demonstrated that atheism entails a contradiction. It requires affirming rational certainty in practice while denying the necessary precondition for rational certainty in theory. It simultaneously claims that rational certainty exists and cannot exist. This is not a paradox or mystery. It is a direct logical contradiction.
==>> And because contradictions cannot be true, any worldview that leads to one, such as atheism, cannot be true either. <<==
(3) CONCLUSION: Therefore, atheism cannot be true and is necessarily false
> Let’s summarise the argument and bring it to its conclusion.
- In Premise 1, we demonstrated that rational certainty must necessarily exist. Rational certainty is the state in which a mind knows something in such a way that it cannot possibly be false. To deny rational certainty is self-defeating, because even the claim that “rational certainty does not exist” would itself require rational certainty in order to be meaningful. You would have to be rationally certain in order to justify the claim that no one can be rationally certain. The very act of denying it presupposes it.
- In Premise 2, we showed that rational certainty depends on two necessary preconditions. First, there must be at least one mind, because rational certainty is a rational state, and rationality is something only minds can do. A world without minds could not contain rational certainty. But that alone is not enough. The second necessary precondition is the existence of an all-knowing mind. This is because finite minds are always vulnerable to error. They are subject to rational uncertainty by nature, since they cannot know what they do not know. Only an all-knowing mind could possess rational certainty in an ultimate and infallible way, and only such a mind could serve as the source or ground of rational certainty for other minds.
- In Premise 3, we showed that any worldview that denies this necessary precondition cannot account for rational certainty without contradiction. If rational certainty requires an all-knowing mind, then any worldview that rejects the existence of such a mind is left affirming an effect while denying its cause. That is a metaphysical contradiction.
- In Premise 4, we pointed out that atheism is exactly such a worldview. By definition, atheism denies the existence of God, and therefore denies the existence of any all-knowing mind. The atheist cannot appeal to such a being without abandoning atheism in principle. And attempts to replace that mind with impersonal abstractions like logic or mathematics fail, because those are not minds and cannot reveal truth.
- In Premise 5, we showed that this leads directly to radical skepticism, the view that nothing can be known with certainty. Atheism, by denying the precondition for rational certainty, collapses into radical skepticism. But we have already shown that radical skepticism is false, because rational certainty is transcendentally necessary. Therefore, atheism leads to a contradiction—it affirms and denies rational certainty at the same time.
- In Premise 6, we restated that any worldview that entails contradiction cannot be true. This is a basic law of reason.
- Therefore, the conclusion follows necessarily:
Atheism cannot be true and is necessarily false.
