Why is there a universe? What caused it to come into being? Is the universe eternal? These are some of the most fundamental questions philosophers have been asking and attempting to solve for the last 2000 years. Many propositions and arguments have been put forward and I would like to focus on one that I have taken a particular liking to. This is known as the argument from contingency.
17th century German philosopher Gottfried Leibniz asked the famous question, “why is there something rather than nothing?” Leibniz came to the conclusion that this explanation is rooted in God, but just how did he come to this?
Let’s look at this argument in terms of the premises and the conclusion.
The argument goes:
Premise 1: Everything that exists has an explanation of its existence, either in the necessity of its own nature, or in an external cause.
Premise 2: If the universe has an explanation of its existence, that explanation is God.
Premise 3: The universe exists.
Conclusion: Therefore, the explanation of the universe’s existence is God.
In order for the conclusion to be true, the premises all have to be true (this is known an as deductive inference). Let’s look at premise 3 firstly. Premise 3 is certainly true; we can know for certain that the universe does exist and it is logically reasonable to conclude this, and so we have a solid answer here. How about premise 1? We run into what seems like a dilemma here when philosophers such as Bertrand Russell make the claim that “The universe is just there and that’s all.” Is this a reasonable assumption however? We will look at this later in more detail regarding the recent scientific evidence but for now let’s take a more philosophical and existential approach.
Human experience of life tells us that whenever we see an object or organism, we know that there must be an explanation for its existence, even if we never see that explanation with our own eyes. Size and chemical composition does not affect this law and so logically this concept of causation applies to the universe as well. If the universe does exist, then we need an explanation for its existence; an eternal universe is illogical.
We run into a supposed second issue at this point. Someone might ask the question, ‘If premise 1 is true, then does that not mean that God needs an explanation as well?’ If this were the case, then premise 1 would read, ‘Everything that exists has an explanation of its existence’. In phrasing the statement like this, it would be logical to ask the question of how God Himself came into existence since God is a thing, even if he is more abstract. At this point however, Leibniz makes a distinction between something existing contingently and something existing necessarily. These definitions are tied to the last part of premise 1, the section that reads, ‘either in the necessity of its own nature, or in an external cause.’ We must now define these two words before we can move on.
For something to exist contingently means that that thing has a cause for its existence; for example, the cause of a mobile phone’s existence is (initially) the thought of a human being followed by the action of the physical creation of the phone in the real world. For something to exist necessarily means that that thing exists by the necessity of its own nature, in other words, that thing exists independent of a cause.
Coming back to the claim made by Bertrand Russell. There is strong scientific evidence today which suggests that the universe certainly did have a beginning. For the most part of the last 2000 years almost everyone believed that the universe existed eternally. Greek philosophers such as Aristotle and much more recent scientists such as Fred Hoyle took this position. This stance seemed logical until about 100 years ago when a series of discoveries by men such as George Lemaitre, and Edwin Hubble involving the redshift of star light provided strong evidence that the universe might in fact have had a beginning at the big bang.[4a] [4b] This proposition cannot be established with full certainly due the fact that all of physics as we know it breaks down beyond the point of the big bang (quantum physics takes over at this point and it hosts an entirely new set of laws). Most scientists and philosophers today however agree with the view that the universe most probably did have a beginning; as Stephen Hawkins puts it, “Almost everyone believes that the universe, and time itself, had a beginning”.
Thus, we can conclude to within large degree of certainty that the universe likely exists contingently.
Now that we have established the nature of the universe, we again need to ask the question, why does it exist at all? It would be logically incoherent to say that the universe caused the universe to exist, since something that is contingent cannot cause itself to come into existence and human experience confirms this. The only adequate explanation therefore is that the universe must rely on a non-contingent being for its existence. This non-contingent being would need to exist necessarily in order to be able to create something like the universe.
What about our second premise, premise 2? In theory, there could be a range of explanations that seem to negate God as the primary cause. Under careful examination however, every one of these explanations fail in some aspect. The reason – as hinted at above – is that every other explanation can be boiled down to either something contingent in the universe, or something abstract within the universe such as a law like gravity. The problem here is that it is impossible for a contingent object within the universe to create the universe itself from nothing as this is self-refuting from the start. Similarly, universal laws are not known to create anything, they are useful explanations of universal phenomena in such a way that the human mind can comprehend (also known as the rational intelligibility of the universe), but they are not adequate explanations for origins in themselves.
To understand this point regarding universal laws and their roles within the universe, let’s take a common law such as gravity. Gravity is a force which causes anything with mass (such as planets) or energy (such as light) to be brought towards each other, or bent (light bends, whereas objects attract). Notice however that gravity does not cause the initial creation of matter. Gravity has never been observed to create anything from scratch, it has only ever been observed to act on an already existing body or type of radiation (light). Similarly, the laws of mathematics do not have the capacity to create money from scratch however, we use it as a basis for physics and maths itself. Einstein puzzled with this concept as well; his thoughts were summed up in a statement when he asked, “How is it possible that mathematics, a product of human thought that is independent of experience, fits so excellently the objects of physical reality?”
The only viable explanation for the cause of the universe would need to tick very specific boxes: It would have to exist necessarily, it would also need to be timeless, spaceless, immaterial and extremely powerful. These descriptions come together perfectly in the form of God, the only plausible explanation for the cause of the universe.
Although not all will agree with premise 2 and the conclusion, in my view the argument is sound. If one logically follow through the steps in accordance with the evidence presented, it becomes clear that the only reasonable explanation for the existence of the universe is God.
With this we can now close by answering Leibniz’s philosophical question, why is there something (a universe) rather than nothing? The answer is: because God created it.
 Gottfried Wilhelm Leibniz. (1714). The Principles of Nature and Grace, Based on Reason. 7
 Okasha, S. (2016). Philosophy of Science: Very Short Introduction (very Short Introductions). 2. Oxford University Press. [p16]
 Fr. Copleston vs. Bertrand Russell. January 28th, 1948. BBC Radio Debate on the Existence of God
[4a] Dr. William Lane Craig. (1992). The Existence of God and the Beginning of the Universe. Available: http://www.reasonablefaith.org/the-existence-of-god-and-the-beginning-of-the-universe.
[4b] Clarification: I myself do not hold to the Big Bang as a valid origins explanation, however, for the purposes of this argument I am adopting this view as it is the consensus within current mainstream science. Also it defends my position regarding a necessary creator for universe.
 [Stephen Hawking and Roger Penrose. (1996). The Nature of Space and Time, The Isaac Newton Institute Series of Lectures (Princeton: Princeton University Press, [p. 20.]
 Max Jammer. (1921). Einstein and Religion, Princeton University PressFirst blog post