I'm surprised you find disbelief unreasonable. If someone says, "Hey, I just saw a cow floating past the moon!" and someone else says, "I don't believe that actually happened" then the reasonableness of the disbelief can't be measured by the concept of disbelief itself, but by our shared conventions for knowledge (epistemology) and how we understand the physical universe.
Equally so, if someone says, "I believe if I jump off this roof, I'll fall towards the earth" then the reasonableness of their statement of belief again relates to what we know of gravity, the physical universe, etc.
Belief or disbelief in a god or gods is possibly a different category because it creates non-falsifiable claims. If these god/gods occupy a super natural or extra-natural place then they are beyond physical reality and can't be measured using the same tools of reason. They don't impact physical reality in the same ways to make the scientific method a useful convention there.
So we're left with personal, individual experiences and their interpretations. Those who have had what they consider supernatural experiences can't understand why others don't believe as they do. Those, like myself, who thought they had supernatural experiences while they were believers and later learned more about the human brain and how it creates stories to explain complex experiences then later wonder why so many people believe. Ultimately, we are held to our own personal experiences and the best way I've found so far to transcend that is to study logical fallacies, the human brain, the scientific method, systems of logic, and to share information through open communication and dialogue. At least that way when my perspectives are skewed and can be demonstrated as such, I can learn and grow.
I've enjoyed the exchange as well. Thank you for demonstrating how two people who many not agree on worldviews can still respectfully communicate and appreciate each other's perspectives.
I find 0% possibility (complete disbelief) and 100% probability (complete belief) about equally (un)reasonable.
I don't understand how an intelligence that exists would be considered anything but supremely "natural", so I guess it depends upon your definitions of "god" and "nature" and ... :-)
I'm not sure "beyond physical reality" and "beyond reality" are equivalent. What if the nature of our reality is non-physical (in the normal conception of "hard" matter)? It makes a difference.
I think using reason (the basis of the scientific method) will always be useful. Take a gander at my post: Can I know the truth of things beyond the physical?
And how would we ever know that? I replied to your post, but it seems quite silly to me. The examples given of "non-physical" things are clearly physical to me, based on the readings and lectures I've seen.
We come to discover the unknown/invisible (presently non-physical) via its effects by the use of reason (anything that affects our reality - if it doesn't, is it "real"?).