http://en.m.wikipedia.org/wiki/Original_affluent_society Quote: studies show that hunter-gatherers need only work about fifteen to twenty hours a week in order to survive and may devote the rest of their time to leisure
http://condensedscience.wordpress.com/2011/06/28/life-expect...
Quote:life expectancy at age 15 is 48 years for Aborigines, 52 and 51 for settled Ache and !Kung, yet 31 and 36 for peas- ant and transitional Agta. Survival to age 45 varies between 19 and 54 percent, and those aged 45 live an average of 12–24 additional years The modal age of mortality in hunter-gatherers can range from 68 in the Hiwi to 78 in the Tsimane.
Incidentally, my experience of job sharing is that it doesn't scale. You get 2 or 3 people, they arrange the job share among themselves, everyone is blissfully happy. Then one leaves and how do you fill the position, when it was tailored for one specific individual's lifestyle? The other sharers then find themselves having to adapt again, and maybe that's incompatible with the other commitments they've picked up thanks to the arrangement. 9-5 is actually the least-worst option all things considered.
If people still feel too idle and can't come up with something to do on their own, they can share a 40hr job with 4 or 5 other people. I am fully confident, though, that everyone will find something they like to do to occupy their time.