How do we know? It is mainly a decision to attribute to Him certain things that happen. I found the assumption that `God acts in the world' a superior way of organizing the events that I see or hear happen.
I once was an atheist, and had no explanation for seeming chance events that carried purpose. When I saw that people in the Old Testament attributed such things to the guiding hand of God, it enriched my world view, and I took it as objective evidence for God. Objective because I hadn't been trying to invent something but I had found an established tradition that brought more unity and understanding into my already well-established patterns of thinking. (In precisely the same way I had again and again recognized other valuable insights that helped me grow and shaped my world view.)
Of course, I was aware that this insight was no proof of God's existence. There are always enough arguments that argue against anything one can say about God. The main reason is that the concept of God is ill-defined from a logical point of view, i.e., there is no commonly agreed upon definition. So anyone who doesn't like one point of view feels free to shift the ground, and mutual misunderstanding is programmed....
Rather, I made my observation a working definition of God. Being an atheist, the concept had been without meaning for me (except as a container of a mixture of recollections from childhood, that I left behind when I left home). So I felt free to associate the word God with the only bit of objective knowledge I knew that was supposed to be God's work, and that I had observed in my life without having it satisfactorily covered by my scientific world view. Thus I started to consider God as a synonym for the power that gives purpose to chance, that is active when chance becomes meaningful or even decides our fate (see also accidents-with-a-purpose). With this preliminary definition I had a solid basis for investigations since it was rather obvious that this God exists, and plays a role in every person's life, mine included. And even an extremely important one...
Still there was a lot to do. I knew hardly anything about this God, except that it was clear to me very soon that I had to find out about `Him' as much as possible. What kind of agent was `He', what was `His' purpose for my life? As the author of purpose, `He' must surely know best, and it would be foolish not to cooperate with `Him'. That `He' was a person (but of course neither male nor female) was clear to me since without personality no purpose; the male pronoun I took from the Christian tradition. Also, having found this important extension of my (previously lopsided rational) world view through the bible, this book suddenly became much more trustworthy to me. I took it as a guide showing me how people thought about and related to the Source of Purpose, and tried to find out how much of it I could match with my experience. And where I didn't have experience, I tried to learn and experiment to find out to what extent I could trust the book, what I could reliably expect from God, and what kind of relating to Him would pay the desired dividends in my life.
And I found the results of my investigations rewarding beyond all expectations...
Science and Faith
My Views on the Christian Way of Life
my home page (http://www.mat.univie.ac.at/~neum)
Arnold Neumaier (Arnold.Neumaier@univie.ac.at)