Here's an interesting perspective on the global economy in the very long run: the pace of technological progress today--the speed with which we increase our productive capabilities--is roughly one hundred times what it was as recently as four centuries ago.
In the year 1 world population was about 180 million. In the year 1650 it was about 540 million. This tripling of world population was accompanied by very little improvement in standards of living: peasants--and most people were peasants--were as short, as malnourished, as hungry, and as sick in 1650 as in 1500. World real GDP only tripled in 1650 years--a pace of real GDP growth of roughly 0.07% per year, two-thirds of which is due to the fact that each mouth comes with two hands. The improvement in productivity in the pre-industrial world? 0.02% per year.
Compare and contrast that to the more than 2% per year of real productivity growth in the world economy today.
I'm Brad DeLong.