So what evidence would it take to make me believe in god?
The short answer is "almost any evidence at all, if it meets a few criteria, and I know before we start what it is we're looking for evidence of".
Here's a longer version, slightly clarified from one I posted elsewhere to a question from a theist.
First, let's agree on what phenomenon we're investigating:
- Which god are we discussing? What are its properties?
- what observations would rule out such a being?
This is necessary because if its properties are undefined, how can *anything* constitute evidence for it? How would one distinguish between evidence for, evidence against and irrelevant information?
Given suitably clear answers to those, I will accept pretty much any evidence that's
- sufficiently extraordinary to match the extraordinariness of the claimed god,
- sufficient to rule out alternate non-supernatural explanations, and also
- sufficient to rule out alternative supernatural ones
i.e. any evidence sufficiently strong to convince me we found what we were looking for (rather than something else extraordinary or even ordinary), and that we're not just fooling ourselves or being fooled by someone or something else.
In other words, if you specify which god hypothesis we're proposing up front, and what evidence could rule the hypothesis out (otherwise it's an hypothesis without any explanatory value at all), I'll then be prepared to consider evidence for it. To cover all those bases, it will have to be multiple, pretty consistent pieces of evidence, but I won't limit it. Lots of things will do.
[One problem I often run into is that frequently the theist asking the question's concept of what constitutes evidence is not what's normally regarded as actual evidence for a phenomenon at all. Feelings aren't evidence, for example. Nor is popular opinion. Nor is "it's written in this book" really evidence, because not everything written in books is true. Historians have ways of becoming reasonably convinced of certain things having happened, rather than relying on statements in a single work of unclear providence.]
Any real evidence. Almost anything that's demonstrably not just at some stage come out of people's heads.
Now your turn, theists: What observation(s), if any, would convince you that your particular god doesn't exist?