Why money messes with your mind

http://www.newscientist.com/article/mg20127001.200-why-money-messes-with-your-mind.html?page=1

Daniel Ariely of the Massachusetts Institute of Technology is one of them. He suggests that modern society presents us with two distinct sets of behavioural rules. There are the social norms, which are "warm and fuzzy" and designed to foster long-term relationships, trust and cooperation. Then there is a set of market norms, which revolve around money and competition, and encourage individuals to put their own interests first.
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The trick is to get the correct balance between these two mindsets. Numerous psychological studies have found a general trade-off between the pursuit of so-called extrinsic aspirations - such as wealth, but also fame and image - and intrinsic aspirations, such as building and maintaining strong personal relationships. People who report a focus on the former score low on indicators of mental health, and those strongly motivated by money are also more likely to find their marriage ending in divorce.

This is not to say that we shouldn't focus at all on extrinsic aspirations. Everyone needs money for those parts of their lives governed by market norms, and it's well known that financial strain can bring depression, perceived loss of control and reduced life expectancy