I participate in the efforts of a local nonprofit organization, and the guy who's running everything holds weekly meetings to discuss fundraising and other challenges. He insists that everyone show up ready to brainstorm and come up with lots of ideas. In other words, he wants people to come to the meetings wearing their "thinking cap" so they can let their brilliance shine.

I don't think it works that way. Creativity is not something that the majority of us can turn on and off just by flipping a switch. We can't control when inspiration or ideas strike; we can only learn to recognize, and do something about it, when it does strike.

It's almost like an emotional state instead of a rational one. Instead of talking about putting on your "thinking cap", I think people should refer to it as your "thinking mood". When you get into a thinking mood, start writing stuff down. If you let people's creativity pour out on their own terms, when they're ready to do so, you'll get much better results. You just need to give them an outlet.