⚘ Part 1
⚘ Part 2
⚘ Part 3
⚘ Part 4
⚘ Part 5
⚘ Part 6
⚘ Part 7
⚘ Conclusion

Part 1

We start by defining 3 categories of existence:

• Necessary - a thing which must exist.
• Impossible - a thing which must not exist.
• Possible - a thing which can exist, but also has the possibility to not exist.

An example of an Impossible existence would be a ‘square triangle’. A triangle has exactly 3 sides and a square exactly 4. These two properties are mutually exclusive, and therefore there is no possible world in which a ‘square triangle’ could ever exist.

An example of a Possible existence would be a human. A human is born, and did not exist before their birth. A human dies, and does not exist after their death. It is entirely conceivable that that human’s parents could have made the decision not to have them, and so there is a possible world in which they never existed in the first place.

We have yet to establish the existence of anything Necessary.

It is important to note that these three categories are all mutually exclusive and exhaustive. There is no fourth category that is not a sub-set of these three categories.

Part 2

Next, we will establish the Principle of Sufficient Reason.

In any discussion, we have to accept certain principles as axiomatic, such as the Law of Non-Contradiction. If (A is true), then (A is not true) cannot be. We accept principles such as these because they are inherent human assumptions. You have been making assumptions like these your whole life. It becomes nonsensical to reject them, because whatever argument one might make would have to rely on these principles. How can it be true that there is no such thing as truth?

The Principle of Sufficient Reason states that everything must have an explanation for its existence. Every being, every fact, every event, they all have a reason to exist as they do. This principle is an inherent human assumption. If you came home to find your door smashed open and all of your valuables missing, you would phone the police because you assume that there is a reason for your house to be as it is, most likely that you were burgled. The last thing you would do is say to yourself, “well, it might have just occurred for no reason.”

If one did try to reject this principle then that argument could be rejected just as easily:

Alan: “I don’t believe in the Principle of Sufficient Reason. You need to prove it.”

Brenda: “You are just wrong.”

Alan: “That isn’t a good argument. Why am I wrong?”

Brenda: “If you are correct, that nothing needs an explanation, then why do I need to explain my argument?”

Part 3

Next, we will establish that anything Possible must be Contingent on another existence distinct from itself.

The fact that a Possible existence could have not existed means that there is a question as to why it does exist. This question needs an answer; there needs to be a reason why it exists. If the explanation of its own existence is itself, then it must pre-exist itself. This is much like a mother giving birth to herself, an absurd regression. We are searching for an explanation as to why the thing exists, but all this offers us is an infinite loop with no real explanation for how the thing can exist in the first place. Therefore, there must be an external explanation for the existence of any Possible existence. We can call a Possible existence a Contingent existence because it must be Contingent on something other than itself.

Part 4

Next, we will prove by contradiction that there must be a Necessary existence.

We will imagine that the real world contains no Necessary existences. We know that there are Contingent existences such as you and me. The existence of these Contingencies requires explanation. If we take a real world example of a human, the reason they exist would be due to their ancestors, and they would exist due to some process by which they were created, and that leads back to the formation of the solar-system, and that is explained by the events following the Big Bang and so on. Essentially we are looking at a chain of prior explanations, and if we follow that chain backwards we are going to come across one of 3 possibilities:

1. Everything depends on nothing. At the beginning of the chain there is a Contingent existence that was not explained by anything. For example, one might say that before the Big Bang there was nothing, it just happened for no reason. This is a clear violation of the definition of a Contingent existence and the Principle of Sufficient Reason.
2. The chain is infinite. There was no beginning, the chain of prior explanations goes back infinitely, with more and more Contingent existences providing more and more explanations. Each time we add an existence at the beginning of the chain to provide a reason for the rest of the chain to exist, we also then add the need for an explanation for that existence. The problem with this becomes clear when we try to count backwards from infinity. We have no starting point. Even if we say $\infty-1, \infty-2$ … as we head towards $\infty - \infty$ we still never get to 0 because $\infty - \infty$ is undefined. This is a problem for us as we are here at a definite point. This infinite set of prior events has been exhausted, which is a clear contradiction of infinity.
3. Inter-dependence. This could be arranged any number of ways, but the problem is always the same. We could imagine two initial Contingent existences which explain each other, like two deities who created each other. We could imagine a cycle, like the universe crunching and then causing a Big Bang that brings into existence that same universe. We could imagine a web, where Contingent existences are all explaining each other’s existence. It doesn’t matter how you arrange it, these are all round-about ways of saying that a thing depends upon itself. If there are two inter-dependent Contingencies, then A cannot exist without B first existing, B cannot exist without A first existing, and therefore A cannot exist without A first existing, but we have already established that this is absurd in Part 3. If there is a cycle, then it would look something like A cannot exist without B, B cannot exist without C, and C cannot exist without A, which once again means that A cannot exist without A first existing. The logic is the same for a web and any other arrangement we could imagine.

The reason none of these work is that with only Contingent existences, you have no ultimate grounding for why all of them should exist. Given that every world with only contingent existences is impossible, and that there are only 3 categories of existence as defined in Part 1, and that Impossible existences can’t exist, we can conclude that there must be a Necessary existence.

Part 5

Next, we will establish certain facts about this Necessary existence:

1. It is sufficiently powerful to create everything else that exists.
2. It is eternal, as if it began to exist or could cease to exist, then before and after its existence it would not exist, but it isn’t possible for it to not exist as that violates the definition of Necessity.
3. It is independent. If the existence of the Necessary being depended on something else, then that implies that there is a condition on its existence. This contradicts Necessity. It could also be argued, but I can’t yet formulate this properly, that there can be no limits on the attributes of the Necessary existence. If it has knowledge, but only of some things and not others, why? What is the explanation for this arbitrary limit? What is its grounding?
4. It is not composed of parts. If the Necessary existence were composed of parts, then it would depend upon those parts to exist, which violates point 3. This also tells us that the Universe can’t be Necessary, as the removal of all matter and energy would mean the Universe did not exist.

Part 6

Next, we will prove that the Necessary existence has a will.

Everything else that exists, which I will from now on refer to as the Creation, is arranged in a specific manner. The speed of light is 299,792,458m/s, there are 8 planets that orbit the sun, etc. We can of course imagine the Creation being arranged in a different manner, or not existing at all.

(One might argue that there could be a multi-verse, in which every possibility is realised, and therefore there isn’t really a specific arrangement. The problem with this is that your specific experience is of only this world, rather than a different one. Even if there is a multiverse, you are perceiving only a part of it when you could have perceived another. There is definitely some degree of arrangement.)

This then leaves us the question of why it is arranged as it is. Why are there 8 planets, and not 7? Why couldn’t the Universe be slightly larger, or slightly hotter? One might argue that it comes down to randomness, but true randomness would mean something existing as it does for no reason. This is simply a violation of the Principle of Sufficient Reason. The explanation then has to come back to the Necessary existence.

What function could there be that can distinguish between possibilities and then select one? This is not some pre-programmed machine. Nothing pre-exists the Necessary existence, so whatever it creates is only from its own deciding-function. What possible function could there be that can do this? The answer, rather beautifully, is within yourself. You know what it means to make decisions, even arbitrary ones, because you have a will of your own. This is the only explanation of how the Necessary existence creates, that it has a free will, because this is the very definition of a will. Isn’t it amazing that the Necessary existence gave you such a rich and intuitive understanding of it?

From this point on we should feel confident in describing this being as a person, as it clearly has a mind of its own. It is not some force of nature, or abstract spiritual concept, this is a real person that created you of its own free will. We will go even further, and call this being ‘God’.

Part 7

Next, we will prove that there is only 1 god.

Let’s imagine that god A wills for the sky to be only blue, and god B wills for the sky to be only red. Which colour will the sky be? If A overpowers B, then a limit has been imposed on the power of B. Its nature is now being determined by A, which makes it dependent. It is also not conceivable that they could both get their way, as the sky being only red and only blue simultaneously is a logical contradiction.

One might argue that their wills might always necessarily align, so they could never disagree. There are three problems with this:

1. Why are we describing them as 2 separate persons if they share a will?
2. If they can’t differ, then they are both dependent upon each other to make decisions, as they are not making the same decisions by coincidence.
3. There is no grounding for why they have to share a will.

Therefore, there is only 1 god; only 1 freely-willing, personal, Necessary existence.

Conclusion

I hope this is a sufficient proof of the existence of God. If you have any questions, or you found that part of the argument wasn’t compelling or had a hole in it, please email me with your thoughts.

If, however, you have accepted these arguments, then that puts you in a rather interesting position. The Enlightenment, upon which our society and the prevailing world order is built, was itself founded upon an incorrect assertion, that it is irrational and unscientific to believe in God. This Cosmological argument was partly created by Leibniz, the father of calculus. It is also the case that Isaac Newton believed in 1 god for similar reasons. These two are giants when it comes to the age of rationality that we now live in. Isn’t it interesting that they were theists? Why does our society treat religion as such an irrational thing?

It is also interesting to note that this is merely the most forceful among very compelling arguments, all of which are enhanced when viewed in light of this understanding. It is not some obscure, hidden thing. These arguments have been in our intellectual canon for hundreds, if not thousands, of years.

But much more importantly, this now leaves you with the inescapable conclusion that you are here for a reason. You are not some meaningless cosmological accident, you are the result of a deliberate decision by the same person that created the laws of physics, coded the human genome, created laughter, and created suffering. What is that purpose? Why did God create us?

Thank you.