" As every individual, therefore, endeavours as much as he can both to employ his capital in the support of domestic industry, and so to direct that industry that its produce may be of greatest value… he generally, indeed, neither intends to promote the public interest, nor knows how much he is promoting it.… He intends his own security; … he intends only his own gain and he is in this … led by an invisible hand to promote an end which was no part of his intention. By pursuing his own interest he frequently promotes that of society more effectually than when he really intends to promote it. —Adam Smith,9 18th century political economist "

― Donella H. Meadows , Thinking in Systems: A Primer