What evidence would you expect to find?
Something that cannot be explained by any other means might work. It's not like he has to make a personal appearance, although he has made them.
As xasop said, I don't believe that's possible.
I mean, remember where you are. The shape of the earth has been known and proven beyond any reasonable doubt for centuries. And yet, here we are...
There is necessarily a faith element here. I know people who have been miraculously healed or transformed - a sceptic will say "but those things can happen anyway". Which I guess is true. I just have faith. You might think that's a bit weak and woolly but it's all we've got.
I don't think one should throw one's brain away, but neither do I think approaching this an a purely academic exercise will get you very far.