Brian Chi-ang Lin

Joséphine De Bruycker & Mathieu Bélanger | 23 mars 2021

Brian Chi-ang Lin is a Sustainability Professor and Business Adviser from National Chengchi University in Taipei, Taiwan. On Tuesday, March 23rd, the 23 members of Poly-Monde attended a virtual lecture on circular economy given by Lin concerning his most recently published article Sustainable Growth: A Circular Economy Perspective

Achieving the Sustainable Development Goals (SDGs)

The SDGs are part of the 2030 Agenda for Sustainable Development and were adopted at the UN Sustainable Development Summit in 2015 ( These 17 goals are at the center of the movement that underlines the necessity to rethink our health and education systems’ ways, tackling inequalities and guiding economic growth ( From a holistic point of view, Lin explains that one of the best ways to achieve the SDGs is to promote a circular economy. In line with this, the article presented by Lin explains that UN members should substitute circular GDP for conventional GDP as it shows to be the best way to include environmental impacts into economic activities.

Circular Economy and metrics

One key differentiator in the circular economy framework is the idea that output “waste,” generated by the production of goods and services, still has a certain value for future use. However, its linear counterpart views the production cycle as one that captures all possible value from intrants, thus leaving output waste worthless. This idea gives us an insight on how to modify the traditional National Income Accounting equation to reflect a nation’s regenerative capacity within a given time period.

Y(GDP) = C + I +G + NX + SD 

In the revisited accounting equation, M. Lin (Lin, 2020) adds the circular output SD, representing domestic demand for sustainable development, to the four traditional factors of consumption spending C, investment spending I, gov. spending G, net exports NX.

M. Lin then regroups the linear and circular factors to produce a global view on the movement of materials and value in the circular economy framework. As circular output is generated in a given cycle and reinserted in the next one, the flow of raw material (input) and output waste (output) are reduced, and certain recycling and circularity rates are achieved. 

  • Circular output/(Circular output + Output waste): recycling rate
  • Circular output/GDPn: rate of circularity for period n + 1

Planning growth for a sustainable future

“In the long run, the amount of pollution decreases and the value of circular output increases, a win-win scenario for promoting environmental protection and economic growth” (Lin, 2020), states the article, underlining the necessary interrelation between the economy and output waste management. Nonetheless, after analyzing the benefits of a circular economy transition, Lin reminds us that institutional planning, combined with technological progress, is essential to promote sustainable consumption and investments.


  • Brian Chi-ang Lin (2020) Sustainable Growth: A Circular Economy Perspective, Journal of Economic Issues, 54:2, 465-471, DOI: 10.1080/00213624.2020.1752542