Momus, possibly the most read blogger out there, discusses how brainstorming is inferior to wearing a mask when solving problems or coming up with new ideas.
But ask any writer facing a blank page, and she'll tell you the same thing. Brainstorming invites the internal editor, where a mask allows for freedom. How often have you sat there thinking up the next plot element and striken every idea because it sucks? It's not easy to come up with new ideas when you're staring at white space with all those possibilities staring back at you, however, slip into character and the ideas start flowing.
A mask becomes a filter, a new way of looking at the world. We're free to express thoughts and emotions we otherwise wouldn't. And we're free to conceal whatever we want. It's a game of pretend in the gardens of childhood.
Sometimes getting into character can be difficult; we just don't know what our heroine is going to do next. The choices seem infinite. Try donning an author's mask. I've done it. You've probably done it, too. There have been scenes that had me stuck, and I'll ask myself "What would [insert favourite author here] do?" Or put on the mask of the villain or the hero.
If storming the castle doesn't work, change your identity and walk through the gate as a knight, a servant, or royalty.