In this video Phil Plait talks about skeptic manners. Which is the best way to get people to think more critically? Do you behave like a dick and call people stupid, laugh at their mistakes etc etc (which I admit, can sometimes be tempting), or do you try to take your time to calmly explain why you believe what you believe.
In Phil Plaits words - how many of you became a critical thinker because someone called you an idiot? I think one guy in the audience raised his/her hand...
Anyway - check out the video below, and if you are interested in astronomy, Phil Plaits blog is the place to go: http://blogs.discovermagazine.com/badastronomy/
Phil Plait - Don't Be A Dick from JREF on Vimeo.