What is my main reason for my current view about whether God exists or not?
It asks me to think about it as carefully and as honestly as possible and to discuss my response with a friend or friends. Hello, friends!
Unfortunately, or fortunately I suppose, depending on how you view this stuff, I don't feel like I can explain my current views on deism without exploring some of my own religious history. This is interesting for me in some ways because after being relatively communicative about this in my younger days, I kind of stopped talking about it for various reasons.
So. I was bought up as an atheist. Both my parents were atheists, Mum in a fairly laid back way, Dad in a more strongly cross at religion and the religious kind of way. Despite this, I went to a Church of England primary school - I lived in a village in Norfolk so there really weren't a lot of options. At the time, it didn't have a strongly religious character though. We had the vicar in for assembly every couple of weeks and we said grace before lunch. We also used to say the Lords prayer in assembly (the proper version - they tried to make us change in Y6 and I refused and said the old version while the rest of the school were reading the new version). To me, it was a little like people believing in Santa or the tooth fairy - that's fine, and it's kind of mean to disabuse people so you just go along with it. Bible stories were, well, bible stories - like fairy stories, only about Jesus.
I got older and went to secondary school, which was a straight forward comprehensive. We didn't do any religious stuff, but the RE teaching didn't cover much comparative religion either because I was still living in Norfolk. I think we did the 5 pillars of Islam, which is a nice, straight forward, self contained lesson :) I was not really close to anyone in this period, although I did have friends, and I used to have conversations with myself about the meaning of things and what to do about life, the universe and everything - kind of undirected talking to the universe sort of thing.
When I was applying for university, I met Nathan, who was already at Oxford and the son of my Mum's boss. I developed a huge crush on him. He was very willing to tell me about Oxford and also invited me to come and socialize at a church youth function thingie. I went along and I really enjoyed hanging out with Nathan and with his friends (who were all also already university students at various places). It turned out a couple of my friends from school also went to this church and I started going along for services. After I'd been doing that for a couple of months, I had a religious experience. I don't remember much about it now and it was very difficult to describe even when I was closer to it in time and could recall it better but during the service, I felt an enormous surge of personal well-being and of being loved and connected to something vast and universal. It was pretty overwhelming and exciting - it felt special - and as a result of this experience and the fact that it had happened in a Christian church during a service, I became a Christian. I felt like it retrospectively fit together some parts of my life, seeing things like my tendency to talk to the open air as a prayer I hadn't realised I was praying. I joined the CU at university when I got there and started going to a pretty evangelical church where I had a full immersion baptism part way through my first year.
However, there were a few problems with this. One was that, outside of my church/CU friends, none of my other friends were Christian and I didn't actually have a lot in common with most of my Christian friends - they were a lot more like my school friends. Nice enough and we got on but we didn't really *connect* whereas hanging out with OUSFG (speculative fiction group - the SF geeks) I felt like I was with people who got me. That meant that it was kind of a strain for me to keep up with things like regular church attendance and by the middle of my second year, that had pretty much dropped off. I also found that I became increasingly uncomfortable with many of the beliefs that came with the Christian label. I found and still find that the things Jesus said often resonated deeply with me but the mythology surrounding Jesus was a huge turn off. The all or nothing attitude to the Bible was also something I found very hard to accept - I found it fascinating and useful as the account of people through a period of history trying to understand their connection with God - as a book of rules and a be-all-and-end-all of ethics it was contradictory and lacking.
I also found that it was increasingly difficult, as I thought through and discussed my beliefs to reconcile the idea of a being powerful enough to create the world and to have full knowledge of past and future with the idea of a being who watches over every little action, judging and praising accordingly. I shifted more to seeing God as a creating force - powerful, but basically incomprehensible. I was very attracted to the picture Berkley paints of God as the substance of all creation (bad, bad paraphrase). I also developed some of my own ideas on predestination vs free will and the problem of evil which were not entirely consistent but were also very different from the way that the Church viewed things. This was all kind of a mish-mash and I went back and forth on things like the divinity of Jesus a lot.
What became clearer and clearer in my beliefs though, was that I found it impossible to reconcile the idea that it would matter to God whether or not we believed in him. I still believed (and do believe) in the importance of living a good life, but I think that even if God exists that good life won't require spending time on your knees or chanting because those things have no value in and of themselves (alright, that's arguable but everything in a philosophy discussion is arguable!). If God is both powerful and benevolent, he won't require glorification. Deserve it, yes, but not require it. I stopped going to Church altogether.
As I've receded in time from the religious experience I had, it has become more difficult to sustain the certainty it gave me of feeling a connection to a being greater than myself. Other possible explanations are available and I admit their plausibility. I now would describe myself as an agnostic. I don't know whether or not God exists and in many ways, I feel it doesn't matter whether he does or not. People should try to live good lives, whether or not there is some kind of deity or afterlife (this is almost axiomatic, but I hope you know what I mean). I thought Amy Ferrer Fowler summed it up well when she said "I don't object to the notion of a deity but I'm baffled by the idea of one who takes attendance".
So I guess the main reason for my view is that I spent a lot of time thinking about it! It's kind of a fiddly one and doesn't really fit on a bumper sticker, but there it is (actually, I think you can get bumper stickers which say "Don't be a dick", which pretty much covers it on some fronts but misses some of the nuance :)).