Richard Wilkinson and Kate Pickett, in their book, The Spirit Level: Why More Equal Societies Almost Always Do Better, demonstrate the “pernicious effects that inequality has on societies: eroding trust, increasing anxiety and illness, and encouraging excessive consumption.” They claim that in more unequal rich countries, results are substantially worse for each of eleven different health and social problems: physical health, mental health, drug abuse, education, imprisonment, obesity, social mobility, trust and community life, violence, teenage pregnancies, and child well-being. See http://www.equalitytrust.org.uk/resource/the-spirit-level
