… is from page 80 of Angus Deaton’s 2013 book, The Great Escape:
We are so used to thinking of progress in terms of rising incomes and extended lives that we can easily make the mistake of ignoring the increase in wellbeing that comes from simply having more people. If it is true that having more people in the world implies that there will be less for each person – because of diminishing returns, for example – then the highest possible per capita wellbing would come about in a world with only one person – hardly what we think of as a good world.