I believe I can quote equally heart-warming, soul-stirring, and mind boggling things such as the likes of Mark Twain. And I believe each one of us can! Yes --- I believe our words have powers because we have unique experiences to live through. Each one of us can be a great storyteller. The idea is to extract lessons from each moment in life and share them with the world. Now, the theme of your quotes could be anything you choose. Mine tends to touch the comical, sarcastic type, and meanders into dark humor.
And then you MUST have your power lines that assert the self-worth you've got! They should pick you up when you collapse, push you when you need a kick, and keep you standing even when it is raining on your parade.
So I rely on the Twitterverse for recording my statements. In the heat of the moment you are capable of saying the solid, unaltered, hardcore truth. And that makes a power statement or a lesson of a lifetime.