[Alhaitham doesn't see why he should distrust Sherlock about what he claims. After all, he has see the effects of what a broken mind can turn people into, no thanks to the effects of the Divine Knowledge Capsules. But more than that, Sherlock has always been straightforward and honest with him—so as far as he's concerned, there is no reason to doubt him.

But with that having been said, it doesn't seem like that sort of acceptance is something that has happened to Sherlock, given the brief display of surprise he'd showed. Alhaitham briefly narrows his eyes at that, but chooses to not comment on it for now since the focus right now is not there.]

I'll be more direct. I'd like for you to describe whatever you can remember of those times when you could not distinguish fantasy from reality. [Alhaitham does, at least, make sure to not sound forceful about this request.] I'm no expert, but I've read some topics about the subject before, and my understanding is that such things tend to have an underlying trigger behind them. If we know that, then perhaps it'll be possible for you to gain some control during such situations.

[Still, he'll leave it up to Sherlock. If he isn't comfortable with sharing, then Alhaitham won't force the subject.]