“People want to live well, and they want to live long. Therefore, we should judge a society by the extent to which it enables people to experience lives that are long and full of well-being… What we want to maximise, across people in all present and future generations, is their number of future WELLBYs – with one qualification. Things that happen in the future are increasingly uncertain the further we look, and we, therefore, apply a “pure time discount rate,” δ. Thus

(1) Future social welfare= ∑i∑t WELLBYit (1−δ)t

where i is the individual and t is the number of years ahead. Well-being is measured on a scale of 0-10.”