Every contrivance of man, every tool, every instrument, every utensil, every article designed for use, of each and every kind, evolved from a very simple beginning.
All of us have bad luck and good luck. The man who persists through the bad luck - who keeps right on going - is the man who is there when the good luck comes - and is ready to receive it.
Something must be done when you find an opposing set of desires of this kind well to the fore in your category of strong desires. You must set in operation a process of competition, from which one must emerge a victor and the other set be defeated.
You can do anything you think you can. This knowledge is literally the gift of the gods, for through it you can solve every human problem. It should make of you an incurable optimist. It is the open door.