Barnes literally thought himself into a partnership with the great Edison! He thought himself into a fortune. He had nothing to start with, except the capacity to KNOW WHAT HE WANTED, AND THE DETERMINATION TO STAND BY THAT DESIRE UNTIL HE REALIZED IT.
He did not say to himself, “Ah well, what's the use? I guess I'll change my mind and try for a salesman's job.” But, he did say, “I came here to go into business with Edison, and I'll accomplish this end if it takes the remainder of my life.”