There is a great sense of intimacy if you can dive in a philosophical conversation with someone you just met some minutes ago.
Why is this?
This person isn’t yet important to you. If you upset them somehow, it’s not going to break a relationship that’s taken time to build up. More importantly, perhaps, you don’t expect that you would upset them. You can project onto them your ideal conversation partner. You don’t yet know (and fear) the ways in which they’re going to misinterpret what you say.
That turned out darker than I’d expected. And actually I mean it in a more positive way. If you seek a midwife for your thoughts then you need the freedom that comes with that sort of fearlessness. Trust and safety are traits of a good conversation partner.