Belief is a bizzare concept for me, one that I find difficult to define and understand.
When I was young, it could be argued that I believed in Father Christmas. However at the time, I treated his existence as fact. My parents told me that he existed, why would I doubt them? For evidence I had the fact that in the morning the food we left out for him was eaten. Was this really a state of belief?
If you argue that a state of belief is taking something to be true without actually seeing it with your own eyes, then yes, I was in a state of belief.
I have never been in a state of belief since.
G.K. Chesterton wrote: Tolerance is the virtue of the man without convictions.
Apart from the man bit, I agree. I am not sure if he meant this to be a negative view of tolerance or not, but it appears so.
I do not believe in anything myself, so I am entirely tolerant of other people's beliefs as long as they do not harm others or oppress anyone.
If you can conceive of something as possible, and believe it to be true, then I will acknowledge its possibility. That does not mean that it is fact, or that it is even probable, but it must be possible if that is what you conceive and believe to be true.
So I acknowledge all existing religions and anti-religions to be possible, thetans included.
However I do not believe in any of them myself. Maybe I will find out when I die, or maybe there is nothing after death, and so there will be nothing to find out. Either way, the notion of belief is as alien as thetans to me.