Observations on sanity

Sometimes, I think, I run into trouble because I assume as a matter of course that everyone I talk to (or debate with) is, in fact, sane. And that's usually the case, but not always.
You think I'd be more aware of and prepared for this possibility. After all, there are times when I don't consider myself fully rational (and am sometimes aware of it, and try to get offline/take a nap while the emotional storm passes).
Still, I think that without the initial assumption of the other party's sanity, we'd never get anywhere. Therefore: observe and amend as necessary.