Ayn Rand, Atlas Shrugged

Do not let your fire go out, spark by irreplacable spark. In the hopeless swamps of the not quite, the not yet, and the not at all, do not let the hero in your soul perish and leave only frustration for the life you deserved, but never have been able to reach. The world you desire can be won, it exists, it is real, it is possible, it is yours.