I suppose my only advice is to find out how much he wants to know about it, then. [He doesn't feel like sharing all the details of what he's learned about his future with a complete stranger so he tries to keep it brief.] The person I know here ended up being from my future, and there were quite a few unpleasant things in it he didn't tell me our timelines were different at first. I suppose he didn't want to upset me. And I don't know if what he did was right or not, but it did make me wary of this sort of situation. Just be sure you both know how much information you want to share, I suppose.