But I ... will not accept an answer without conclusive proof.
Well fair enough, this is where you and I differ. G-d requires of us that we take a leap of faith, and I'm prepared to do so and you're not.
In all seriousness, I think your problem is that you have too many questions and not enough answers. No doubt you've read the Bible, and, being an intelligent person, you must have had hundereds if not thousands of questions. What you have to understand is that every single one of those questions has been asked, and answered. And I believe that you are doing your intellectual self a huge disservice by not trying to find those answers. As someone who is a great believer in progress, I'm sure you'll appreciate that progress is achieved by trying to find the answers to questions, not by being content with the question itself.