Well because i dont belive that his memories are what they say they are, as to me they are not logicaly possible . the anwser I get normaly during these arguments Is that I don't belive it because i don't understand it or i'm too narrow minded to accept it . when I ask for proof he says its not down to him to prove it but down to me and others to take aleap of faith. i'm not a shrink and i'm not a mug.
p.s. he is my housemate lives upstairs
(You are French, or Quebecquois, or some other ex-french colony I assume from what you wrote on another thread.)
If what you say he says is true, he's being pretty dogmatic himself. I assume be believes because of his experiences, or at least very much because of what he's experienced. So he should understand that you wouldn't believe him instantly without similar ones - or some form of proof, such as specific new knowledge, which it seems you demanded.
He is not basing his beliefs on a leap of faith, so why should you?
But now I understand that it is not really a worry, but more like each of you is judging the other.
You judge him as deluded
He sees you as narrowminded.
Me, I don't know if either of these are true. Maybe both are true. Maybe each is true to some degree.
Here's a suggestion.
Why not both of you stop labelling the other one. Then you can both take an exploratory approach to your relationship around his ideas. he can try to figure out how to make his ideas interesting, compelling, or valid to you. He could try to figure out a way to have you have a similar experience. You could explore by following his instructions and, if they do not lead to anything new for you, you can say this to him, not as proof that he is wrong, but information he can use around spreading his ideas or sharing them. You could also just ask him a lot of questions about his experiences and ideas, even investigate the implications, together: what would it mean if they are true. In the spirit of exploration or brainstorming.
As long as he isn't leaping off buildings or running at people with a knife, I would avoid focussing on the truth of his ideas - in some final way - but rather focus on making the relationship work.
Even if his ideas are not grounded in reality, I think this exploration could be interesting for you and educational. How does one communicate internal experiences? What is valid epistemology? What assumptions do you have about reality yourself? (even if they are all true, in the process of discussion and exploration, you will get to know these assumptions better, and that is a good thing)
And even if he is right, it is still good for him to learn about how to communicate. And one can learn how to do by teaching. He may become conscious of what he is doing, all steps in it as he teaches it or describes it to you.
Or you can both stay in the 'I'm right you're ______' mode. I mean that can be the right thing. I would not for example sit down with a Nazi and try to 'learn how to be racist', but given that this difference you have is not like that, hey, why not get along and learn from each other.