Cowperwood wondered at first why Rivers should work for Tighe--he appeared almost as able--but afterward learned that he was in the company.

Tighe was the organizer and general hand-shaker, Rivers the floor and outside man.
It was useless, as Frank soon found, to try to figure out exactly why stocks rose and fell.

Some general reasons there were, of course, as he was told by Tighe, but they could not always be depended on.
"Sure, anything can make or break a market"-- Tighe explained in his delicate brogue--"from the failure of a bank to the rumor that your second cousin's grandmother has a cold.

It's a most unusual world, Cowperwood.

No man can explain it.