In the ideal society outlined by Plato, the ruler would be a "philosopher king," - someone enlightened not in the use of power but rather in the cultivation of human goodness. Today kings are passe; everyone knows that the real power is in the hands of fund managers. So Plato would no doubt be pleased that the Norwegian government's Petroleum Fund, a nearly $200 billion fund which preserves Norway's oil income for future generations, has now hired a prominent philosopher, Henrik Syse, as an in-house advisor on ethical issues. According to a recent article in the Wall Street Journal, Syse's appointment was prompted by ethical guidelines imposed on the fund by Norway's finance ministry. A little background is in order. Oil wealth can be fun, but it also has its risks. There is surprisingly little overlap between the list of the biggest oil exporters and the list of the kind of countries most Post readers would like to live in. (FYI, the top 10 exporters are: Saudi Arabia, Russia, United Arab Emirates, Nigeria, Mexico, Iraq, Libya, Algeria and Oman.) Oil wealth can bring not only social ills but also economic ones, such as the "Dutch disease," named after the de-industrialization which visited Holland after the discovery of North Sea gas there. Norway, acting with unusual foresight, decided that oil export revenues would not be siphoned off by oligarchs or even by an orgy of wasteful public spending, but rather would be saved in a special fund to benefit future generations. I often say that the first level of business ethics is to recognize that business itself is ethically desirable; it provides valuable goods and services and promotes friendly intercourse. By the same token, the most basic level of "Socially Responsible Investing" (SRI) is recognizing that investment itself is a socially responsible act, reflecting a concern for future generations. This was achieved in Norway by establishing the fund. But today's investor wants more than a decent return; we also want to know that our money is being used to promote values we cherish. This sentiment is behind the burgeoning Socially Responsible Investing movement worldwide. Today it is estimated that over two trillion dollars are invested in funds that have some kind of ethical screening criteria. A prominent early example were Quaker groups, which refused to invest in firms involved in the slave trade. Here are some common screens in use today: OUT: arms companies, sweatshops, child labor, destruction of environment; IN: contribute to community, good hiring practices, etc. Like any ethical investor, the Norwegian fund has two types of dilemmas: deciding what policies to promote, and deciding how to promote them. In the meantime, the fund is not disqualifying tobacco companies, but is divesting from a number of arms manufacturers (some of them leading suppliers to Norway's military). Some policies are enforced by divestment, but many other initiatives are promoted by trying to influence companies from within via the leverage provided by Norway's investment and often in alliance with other ethically concerned investors. All these decisions are part of Henrik Syse's working day. One revisionist point of view opines that Plato's Republic was really a subtle political document, campaign literature meant to promote Plato as the best candidate for leader of Athens. (Campaign literature since then has become considerably less sophisticated.) But I can be completely open: If any reader wants to make me an advisor to a 12-figure investment fund, I'll be happy to send a CV.