Firstly, please consider what you mean by ‘God’, and what is your reason for asking. Do you really want to know, or have you already made up your mind?

I do want to know. And what I mean by the word is what most people mean by it.

But people mean many very different things. Let’s start off by using the word to mean the Absolute, the Infinite, the Reason why everything exists.

But why does the world need a Reason? Maybe it ‘just is’. Maybe the universe has existed for ever, without any First Cause.

Actually the question of whether it has always existed is irrelevant. If it had, it would still need a reason for existing. The question of God’s existence is to do with whether the universe ultimately makes sense or not, not whether it had a beginning in time. (In fact, as Saint Augustine pointed out, ‘time’ is just one more part of the universe that needs to be explained - and that’s true whether it is finite in extension or not, whether it had a ‘beginning’ or not...)

The idea of ‘God’ is a lot less bizarre to some people than the idea of a universe that exists without a reason.

OK, but God looks a lot like wishful thinking to me.

The same might be said of a person who is looking for water in the desert. You could say he thinks it is out there just because he wants to be able to find it. But that doesn’t mean he should stop looking. The very experience of thirst proves that water must exist out there somewhere. Whether he will find it is another question. You may even deceive yourself chasing a mirage. None of that proves it does not exist, or that it is not worth searching for. Why would we have the desire, if it did not correspond to something that we lack, but which we were designed (or evolved!) to search for? In the same way, it is worth searching for meaning.

Shouldn’t we just look to science for the explanation?

Science can’t go this deep. Let me explain. Even if you had the so-called ‘Theory of Everything’ - the equation for the scientific laws that showed how everything unfolded necessarily from a Big Bang, and how the Big Bang itself was a random fluctuation in a quantum vacuum (or some such thing) - you still would not have explained the reason for the laws of physics themselves. So there is always a further level to push the question.

Assuming ‘God’ exists, then, what causes God? What is his ‘reason for existing’?

You are still thinking of God like an old man in the sky, which is to say that you don’t have a clue what we mean by God. When I say we need ‘God’ as an explanation for the existence of anything at all, I mean that we need a different type of explanation. For the world itself to have a reason or a cause, that cause can only be something that itself does not need a cause. So what kind of entity would not need a cause? That gets us into wondering, into what’s called ‘philosophy’: What is it to be a ‘cause’ of something? What is it to ‘need’ a cause?

To cut a long story short, the only entity that would not itself need a cause would be one whose nature is not to be this or that particular thing, but just to be. When you say that the world ‘just is’, you are appealing to the same idea. But the universe is not the sort of thing that can ‘just be’, because it has a particular nature: it is this way, not that. It is limited, and that limitation needs an explanation. When we say ‘God’, we are hypothesizing something that ‘is’ in a completely unlimited way, whose actual nature is to be. But if its nature is to be, then it doesn’t need any further explanation; it is its own reason for existing, its own ‘cause’.

You just said you were hypothesizing. Does that mean we still don’t know whether this wonderful self-explaining First Cause actually is, or not?

If the world does have a reason, then God would have to be it. What is more, if we are right in our thinking, God would have to exist whether or not the world does. But none of this tells us very much about what we are calling ‘God’. If you want to know more, and if you want to have some kind of actual experience of God, then (using the analogy of science) it isn’t enough just to think about it - you need to ‘test’ the hypothesis, and you do that in one way and one way only: by learning to pray.

That may sound a bit unscientific, but it isn’t really. The scientist uses a telescope to detect a star that his calculations tell him is out there. He uses a microscope to look for things that are very small. He uses the appropriate tool for the task. The only appropriate tool with which to discover God is the instrument of prayer. God is not a physical object that can be seen at the end of a telescope. If God exists, we are talking about an entity, or a level of reality, deep within everything else that exists, including ourselves. So we can detect God by looking within: looking within ourselves, or within other people, but in any case looking deeper than the everyday world of objects. That is why every religion has a form of prayer or interior journey, a discipline that you have to learn and which isn’t always easy. You can’t expect results unless you learn to pray, just as truly as you won’t see the moons of Jupiter unless you are prepared to make the effort and pick up the telescope and learn to use it.

Let’s say you have convinced me that the world may have a Cause. (We’ll have to come back to the question of prayer later!) I still don’t see why this Cause has to be conscious, intelligent, alive. It sounds to me more like a Force, and Energy. An ‘it’, not a ‘he’!

We’ve said that the Cause has to be infinite, which means ‘unlimited’ (in-finite). Any restrictions on what we call the ‘act of being’ and those restrictions would need a further explanation. But to be conscious, intelligent, alive is to be less restricted than to be a mere physical energy or object. A stone can’t move and think, and energy can’t love: those are limitations.

Of course, in Star Trek we meet imaginary beings made of pure energy that can think and act. That is quite helpful in thinking about God, but it doesn’t get us all the way. Those energy-beings still have limitations, but God has none. Like the number ‘Infinity’ we can’t grasp it, because it always lies beyond whatever number - no matter how big - we try to think of. In a way, we can only say in which direction it lies, not what it actually is. That’s what we mean by called God ‘transcendent’. Everything we compare God too, even a human being (an old man in the sky with infinite power, for example), is just a crude analogy, and a highly misleading one at that. Unless this ‘God’ decides to reveal something more about himself to us, most of what we know about him is simply negative: he is not this, not that.

What we can be sure of is that God won’t be more limited than we are. He won’t be less conscious, or intelligent, or loving, than we are.

What if he is more hating? Why assume God is a nice person? What if he is evil?

Because evil is another kind of limitation. Of course, God is not ‘nice’ in some silly, bland way. (‘Aslan is not a tame lion’!) That would be a limitation too. As usual, human words don’t really apply to God. But words like peace and love and justice would apply slightly more than their opposites, which suggest something damaged, or cramped, or in conflict.

Actually, in one way he is more ‘hating’ than us. He hates sin and evil more than we can possibly imagine. But he doesn’t hate the wrong things, as we so often do. And he doesn’t hate any of the things he has made – including us. (Cf. the article on the Problem of Evil.)

Can we know that God exists, or know anything about him, just from looking at the world?

Yes we can - but everything depends on the clarity and depth of our vision. Saints and mystics have told us that to them the world speaks: it conceals God, but it also reveals him. Henri de Lubac writes:

‘God comes to us on all sides through the world; it is his Being that comes to solicit our attention. We ought to be able to meet him everywhere. Whether we consider the "great world" or the "little world", the cosmos that surrounds us or our own spirit, everything real that comes within our orbit is by the whole of itself, and first of all by virtue of its existence, the symbol and the sign of God; not an artificial sign of some kind or another, deliberately chosen and valid by convention, but a natural and, for us, a necessary symbol. It is an ontological sign which we cannot discard or emancipate ourselves from. God is not seen directly or apart from a sign; but God can be seen everywhere, through the world, however obscurely.

‘Every creature is, in itself, a theophany [i.e., a revelation of God]. Everywhere we find traces, imprints, vestiges, enigmas; and the rays of the divinity pierce through everywhere. Everything is drenched in that unique Presence. Everything becomes transparent "to a pure gaze and a steady eye". If our knowledge, like our ignorance, troubles our contemplation, if our mind’s eye cannot see beyond the outer shell of the world, if we are open to nothing sacred - or if, on the contrary, the world seems "full of gods" - that is because our sight is blurred.

‘It is only too true: the world conceals God more than it reveals him. Things have become opaque. And yet it remains true that the Creator "has scattered the reflections of his divine perfections upon his creatures, and that thanks to those visible lights we are able to know, by analogy, the splendours of the inaccessible Creator." The invisible things of God are made known by the things which are made (Romans 1:20).’ [From Henri de Lubac, The Discovery of God (Eerdmans/ T&T Clark, 1996), pp. 87-9.]