I love observing a moment with someone-
You haven't known them long, so you are just in the "getting to know you phase" and you are engaged in a good conversation- a pleasant exchange of information that leans on the polite side of things.
And then it happens- you start on a conversation topic that changes everything. It is the moment where all the polite, superficial conversation is forgotten because they've magically been transformed by the topic of conversation- and suddenly, you see their passion.
It is truly transcendental-
They don't even realize they've crossed a threshold, because of the joy and conviction that has overwhelmed them; and they share their heart without worry for the restrictions of polite etiquette. In a single moment, the stranger before me has revealed their naked heart for my pleasure and review.