If you read just one thing today, it should be the remarkable open resignation letter of Goldman Sachs’ executive Greg Smith, who was head of the firm’s U.S. equity derivatives business for Europe, the Middle East and Africa. After a highly successful 12 year career with Goldman, Smith — a Rhodes scholar — explains that felt he could no longer tolerate working Goldman because of the severe downward trajectory of its corporate culture, and the company’s loss of moral fiber. “I can honestly say that the environment [at Goldman] now is as toxic and destructive as I have ever seen it,” he wrote, explaining that best interests of clients is now not even on Goldman’s radar screen. The only thing that matters now behind closed doors at Goldman, Smith says, is how to make money off of clients. The clients’ goals, desires and best interests are of absolutely no interest anymore. “It makes me ill how callously people talk about ripping their clients off,” Smith writes, confessing that over the previous 12 months he’s personally witnessed five different managers refer to their own clients as “muppets,” even doing so over corporate email. He lays the blame for the company’s completely loss of integrity on the current CEO, Lloyd C. Blankfein, and Goldman’s president, Gary D. Cohn. Smith formally resigned the day his open letter was published in the New York Times.