Trading one capital for another

"Piketty may be right about the long-run evolution of the capital-income ratio β. Since 1970, the slow growth relative to savings in rich countries may have led to substantial accumulation of capital relative to income. But as my estimates for the trend in s*/g* show, this wealth has been amassed over the past 40 years through considerable depreciation of valuable energy, mineral and forest resources. In a sense, these economies have traded one form of capital—the earth’s riches—for another—human riches." - See more at:http://triplecrisis.com/natural-capital-in-the-twenty-first-century/#more-9953"