Self-conviction is the key to acheivement. History abounds with tales of experts who were convinced the ideas, plans and projects of others could never be achieved. However, success came to those who said, "I can make it happen".
Other master sculptors worked diligently on a particularly difficult piece of marble but all gave up saying they could do nothing with it. All that is but one. Michelangelo visualized the possibilities in this same stone and from his convictions came one of the world's masterpieces, the statue of David.