The New York Times has the article Capitalists and Other Psychopaths by William Deresiewicz. He starts with the following paragraph:

There is an ongoing debate in this country about the rich: who they are, what their social role may be, whether they are good or bad. Well, consider the following. A recent study found that 10 percent of people who work on Wall Street are “clinical psychopaths,” exhibiting a lack of interest in and empathy for others and an “unparalleled capacity for lying, fabrication, and manipulation.” (The proportion at large is 1 percent.) Another study concluded that the rich are more likely to lie, cheat and break the law.

By a stroke of luck, I happened to stumble across an interview on C-SPAN of E. O. Wilson in which he talked about his recent book The Social Conquest Of Earth. This book explains why the article above is true. The interview was quite a revelation to me.