Hi Evan,
I'm one of the founders of a new online platform called Letter. I'm in the process of building a community around thoughtful conversation. We have a private Facebook group for our writers, and we host a meetup event (online) every few weeks. I'd like to welcome you and anyone else from the rationalist community to join.
Another fantastic community is Fair Game - a private Facebook group for respectful, "good faith" discussion.
Warm regards,
Dayne
Thanks for your interest, Evan.
If you're referring to joining Fair Game go to the FB page click join, and answer a few questions. If you'd like to join Letter's public community group you can do so here.
Letter's writers group is private - if you write a letter in good faith you'll receive an invitation ;)