It is important to commit to things, and only set goals you can commit to, otherwise your goals will fall to the wayside because they are not important enough to you. Commitment can be a difficult thing because it is so easy to defuse, for example, to commit to cleaning the house then you begin to feel down or whatever and your commitment of cleaning the house falls apart. I guess what I'm saying is only set goals that are important enough to you to commit to, otherwise you will be defeating yourself by not being able to follow through.
Impossible is just a big word thrown around by small men who find it easier to live in the world they've been given than to explore the power they have to change it. Impossible in not a declaration, it's a dare.