Be very careful what you assert, even if it's true. It's really easy to start with good ideas and end up with a doctrine.

If you make a statement like "we should believe cryonics is desirable" or even something as basic (for LW) as "we believe in reductionism", it's really easy to exclude or piss off all the people we actually want to reach.

A very minimal set of skepticism might work. Something like RAW's advice in Prometheus Rising: "Avoid coming to any strong conclusions prematurely. [...] Believe it possible that you do not know everything yet, and that you might have something still to learn."