 A few years later, he began trading for his own account at the MidAmerica Commodity Exchange, an entry-level floor where "mini" contracts were traded.To circumvent a rule requiring traders to be at least twenty-one years of age, he worked as his own runner, and hired his father, who traded in his stead in the pit.Dennis earned a bachelor's degree in philosophy from DePaul University, then accepted a scholarship for graduate study in philosophy at Tulane University, but then changed his mind, and returned to trading.