Ottawa
My apologies. I used "developed" countries in the first post but not after. The authors looked at 181 countries starting with the poorest and found that living conditions improved with increasing wealth up to a point. (Charts are at "The Spirit Level"). Searching they found correlation between living conditions and income inequality across 23 developed countries. Sweden  and Japan had the lowest inequality and best living conditions. The US had the strongest economy, highest income inequality and the poorest place to live. along with Portugal.  Note that Japan was an economic basket case. and  tied for best place to live.  There was no correlation between living conditions and wealth in developed countries.

So we should move on to try and lessen income inequality. A challenge.