i think I have read this premise10 years back.. it definitely is thought provoking. (ie. that the sweet point is 50-70K) and having more doesnt necessarily help as you keep up with the Joneses and there is no end to that.
but read this.. excerpt from the book
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http://www.amazon.com/Farewell-Alms-Economic-History-Princeton/dp/0691141282
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The final great surprise that economic history offersâwhich was revealed
only within the past thirty yearsâis that material affluence, the decline in
child mortality, the extension of adult life spans, and reduced inequality have
not made us any happier than our hunter-gatherer forebears. High incomes
profoundly shape lifestyles in the modern developed world. But wealth has
not brought happiness. Another foundational assumption of economics is
incorrect.
Within any society the rich are happier than the poor. But, as was first
observed by Richard Easterlin in 1974, rapidly rising incomes for everyone in
the successful economies since 1950 have not produced greater happiness.11 In
Japan, for example, from 1958 to 2004 income per person rose nearly sevenfold,
while self-reported happiness, instead of rising, declined modestly. It is
evident that our happiness depends not on our absolute well-being but instead
on how we are doing relative to our reference group. Each individualâby acquiring
more income, by buying a larger house, by driving a more elegant
carâcan make herself happier, but happier only at the expense of those
with less income, meaner housing, and junkier cars. Money does buy happiness,
but that happiness is transferred from someone else, not added to the common pool.