Why is there something rather than nothing? It’s a bit of a head scratcher. Can we answer this question?
In the 18th century, German mathematician Gottfried Wilhelm Leibniz observed that the answer cannot be found within the universe itself because the universe is full of things which also began to exist. The explanation for the existence of the universe must therefore be found externally to it. So, for Leibniz, God becomes a necessary explanation for why anything exists at all.
His argument goes like this:
(1) – Everything that exists has an explanation for its existence.
(2) – If the universe has an explanation of its existence, then that explanation is God.
(3) – The universe exists.
(4) – The universe has an explanation for its existence.
THEREFORE – God is the explanation of the universe.
People will often try to tear down this argument by attacking premises (1) and (2).
Premise (1) – Everything that exists has an explanation for its existence.
First attack – if (1) is true, then surely that means God himself must have an explanation of his existence too!
Not so fast. Leibniz said two different kind of things exist:
A – Things that cannot NOT exist (like numbers). They have a necessity in their nature, so they must exist.
B – Things that are CAUSED by something else and aren’t necessary (like people, planets and house plants).
So in answer to the objection – no. God does not need an explanation for his existence, because he is necessary in his nature for the existence of the universe, and so he must be uncaused.
Second attack – (1) is true of everything IN the universe, but not of the universe itself.
This sounds like a case of (what Craig describes as) the Taxicab fallacy, which happens when someone seems to arbitrarily jump in and out of a system of thought when it suits them. In this case, someone may just arbitrarily decide the universe cannot have any explanation for its existence when they don’t like the idea that God created it. So this objection doesn’t hurt the argument, but it does reveal our metaphysical preferences.
Third attack – the universe cannot have an explanation, because for it to do so requires a prior state of affairs. But nothing existed prior to the universe.
Well – this statement seems to just presuppose atheism! We require atheism to be true, and assert that nothing existed prior to the universe. But this is simply begging the question, and its misrepresenting Leibniz. For him, the prior state of affairs involved God.
So we’ve seen that these attacks on premise (1) are not successful.
So, what about attacks on premise (2)?
Premise (2) – If the universe has an explanation of its existence, then that explanation is God.
First attack – it’s not God who exists necessarily by his own nature. It’s the universe that exists necessarily!
So here, it sounds like the universe is being seen as a God substitute. The problem is, we can’t really view nature this way.
Why? Think of the things that we know about that exist in the universe. The planets, stars, people, animals, plants…are any of them necessary? To say something is necessary in its nature, is to say that this thing cannot NOT exist. Well – all of the things we observe in the universe COULD very well NOT exist. And – the way things work – none of them will exist forever!
If the things in the universe do not exist necessarily, then how can we logically conclude that the universe itself exists necessarily? That seems arbitrary…the taxicab fallacy again?
Second attack – I’m not interested in (2) because actually, if atheism is true then the universe has no explanation of its existence.
Well now the atheist has a problem. He said this:
If atheism is true then the universe has no explanation of its existence.
Well – in that case, an equivalent statement would look like this:
If the universe DOES have an explanation of its existence, then atheism is NOT true!
From our discussion, it seems very reasonable to propose that the universe DOES have an explanation of its existence, so it is not looking good for atheism.
Third attack – what does it even mean to say the explanation of the universe is God?
Well surely it means the explanation is not composed of matter, energy and is not part of space and time. All of these are natural aspects of the universe itself. God is outside of these aspects. That makes him:
- Beyond space and time
- Yet…God is a personal and wilful and creative being
These sound like very basic descriptions of a religious definition of God. And – specifically – they give a basic outline of the Christian conception for what God is like.
These attacks on Leibniz argument aren’t very successful.
Why is this? I think it is because it seems very reasonable to assume that the universe exists and has a cause that is located outside of it. And this cause is a necessary, nonphysical, immaterial being that is beyond space and time. Which sounds like most people’s definition of God!
 William Lane Craig, On Guard Defending Your Faith with Reason and Precision, (Lee Vance View: David C. Cook, 2010), kindle edition, loc 839 – 1058, synthesised and summarised.