A part of the Philosophy of Religion course that's hard to get your head around is Necessary Existence and Possible Worlds. These ideas turn up as part of the Cosmological Argument (especially Aquinas' Third Way) and the Ontological Argument (especially in the version by Malcolm and Plantinga) and finally in Solutions to the Problem of Evil especially in Leibniz's Best of All Possible Worlds argument). Rather than adding to the description on several pages, I'll add some thoughts here.
The idea of 'Possible Worlds' is based on this world not being the only way things could have turned out. The idea of alternative possible worlds is pretty entrenched in DC superhero comics - especially in the adventures of the Flash. However, it plays a big part in Star Trek and even Buffy the Vampire Slayer as well as lots of episodes of Doctor Who. Possible worlds are alternative universes where some significant change made everything turn out differently from the universe we know. The entire plot of Back to the Future Part II depends on this idea.
Possible Worlds illustrate the idea of contingency - that things depend on other things to be the way they are or even to exist at all. For example, it's not difficult to imagine a possible world (let's call it Earth-B) in which you or I don't exist. Our parents married someone else - or married the same person, but under different circumstances - and ::poof!:: we're not here any more (but we are perhaps replaced by someone else who has our name).
Except, perhaps, God.
If God exists, then he'd still be there in Earths B, C and even D (though there would be no people to worship him in Earth D). This is what we mean by saying God has NECESSARY EXISTENCE (otherwise known as ASEITY). If God exists, then he exists in every possible world. Or, put it another way, it's impossible to imagine a possible world in which something could happen to cause God not to exist or make it impossible for God to exist there.
This is because God is non-contingent. He doesn't depend on anything else for his existence or to be the way that he is, so no imaginable change in the surrounding circumstances could make any difference to God.
Leibniz's argument about this world being the BEST of all the Possible Worlds needs more unpacking - in the next blog
It took longer than I thought, but the Design Argument and Cosmological Argument sections of the site are complete. Ontological Argument comes next.
I've over-done the detail (I think) and won't be teaching everything on here (like, who needs Aquinas' 4th Way?). But the information is up for students to extend their knowledge.
The most important question is, Is it clear? It's easy with philosophy to write stuff that makes sense to YOU but not to anyone else - try reading Kant's "Critique of Pure Reason" if you don't believe me. I'd welcome any feedback on the site that asks for clarification. Which bits don't make sense or need to be expanded?
Composing these pages set me to wondering, what exactly is the point of these arguments for the existence of God?
One thing they don't seem to do is make people convert to Christianity or any other religion. I mean, people convert to religion all the time, but almost never because they've been presented with a really impressive philosophical argument. People usually convert because of a relationship that they're in, because they enjoy taking part in worship or because they've had a religious experience. I've never met anyone who was argued into being religious.
There are a couple of exceptions, perhaps. Bertrand Russell is supposed to have run down the street as a student, throwing his tobacco in the air, because his mind was so blown by the Ontological Argument. But he didn't convert to Christianity.
A lot of this material comes from America and I get that too. In the USA, an important part of the Constitution is the First Amendment - the "separation of church and state". America was founded by people escaping religious persecution and prides itself on being a secular country in which everyone can practise their own religion in private, but only in private. A lot of Americans feel nervous about the idea of 'God' being smuggled into discussions about science or politics or ethics. They worry that, before you know it, they'll be teaching 'God' in schools and religious freedom will be a thing of the past. So there are Americans who will argue pretty furiously about the idea of the "Big Bang" being proof of God. And some churches really do want to put 'God' back in the science classroom. Look at the controversy over Intelligent Design.
But these arguments have another value for religious people. Even if they don't create religious faith, they can sustain it. Lots of people come round to a belief in God, but then there are setbacks, temptations or just long periods of boredom. It's easy to change your mind and dismiss your beliefs as a "phase". These arguments help people keep hold of their religious beliefs, by reassuring them that these beliefs are in fact rational and reasonable.
Faith ... is the art of holding on to things your reason has once accepted, in spite of your changing moods - C.S. Lewis
What Lewis means is that you might have good reasons for becoming religious, but those reasons might fade. The argument's for God's existence stop you from ditching your faith during bad times.
When you look at it this way, the arguments don't seem so threatening. They're not trying to convert you; they're trying to encourage and motivate people who are already religious.
With this in mind, we can adopt a healthy attitude towards them. We don't have to crush and demolish these arguments. We just have to understand them. They make good points as well as bad. None of the fails utterly. They don't need "debunking" but they do need to be weighed up.