The author sets a poverty line at 30 daily international dollars (which adjust for cost of living and inflation) and mentions the UN tracks extreme poverty at 2 IUSD. He claims a quintupling of world GDP is needed to solve poverty assuming very low inequality, and how extreme poverty was about 76% in the 1800s and is currently below 9%, whereas 85% people live beneath the 30 IUSD/day line.