Abby Joseph Cohen, Goldman Sachs' senior investment portfolio strategist, says the economy is at a point of structural change and she's disappointed that Janet Yellen won't be picked again for Fed Chair. Danny Blanchflower, a professor at Dartmouth College, says the Bank of England rate raise in an already slowing economy will slow it even more. JPMorgan's John Bilton says the U.S. has a reasonable labor force growth compared to other markets. Finally, Gordon Wood, author of "Friends Divided: John Adams and Thomas Jefferson," says the U.S. really needs a multiparty political system.