Found an interesting TED speech on Youtube:
The video is about "how your body language affects you." It's known that your gestures have great impacts on what other people think about you. But they revealed that unverbal language also play a role in what you think of yourself -- or it shapes yourself --.
I like a couple of sentences that appear in the last part of the video.
1. Don't fake it 'til you make it. Fake it 'til you become it.
2. Tiny tweaks can lead to big changes.