Westport, Connecticut–based Bridgewater Associates, the world's largest hedge fund firm, is almost as well-known for its eccentric founder and quirky corporate culture as it is for its strong investment record. Raymond Dalio, who founded Bridgewater out of his Manhattan apartment in 1975, espouses the philosophy of "radical truth," a policy in which the firm's employees are encouraged to challenge one another's ideas, however painful the process may be, to arrive at the truth. Dalio also famously authored Principles, a 123-page handbook of his life rules, which employees must read. Dalio freely admits Bridgewater's culture is not for everyone, but he likens the experience to going to the gym — painful at first but ultimately worth the effort. For all the controversy Bridgewater's culture has generated, Dalio's policies seem to be working: The firm manages…