Changes

:"[B]y directing that industry in such a manner as its produce may be of the greatest value, he intends only his own gain, and he is in this, as in many other cases, led by an ''invisible hand'' to promote an end which was no part of his intention. Nor is it always the worse for the society that it was not part of it. ''By pursuing his own interest he frequently promotes that of the society more effectually than when he really intends to promote it.'' I have never known much good done by those who affected to trade for the public good." (Emphasis added)

:"[B]y directing that industry in such a manner as its produce may be of the greatest value, he intends only his own gain, and he is in this, as in many other cases, led by an ''invisible hand'' to promote an end which was no part of his intention. Nor is it always the worse for the society that it was not part of it. ''By pursuing his own interest he frequently promotes that of the society more effectually than when he really intends to promote it.'' I have never known much good done by those who affected to trade for the public good." (Emphasis added)

However, [[game theory]] suggests that this is not always true; in circumstances where individuals are not allowed private property rights each individual acting in their own self-interest does not result in the socially optimal outcome. One such example is the [[problem of the commons|tragedy of the commons]].  

However, the occurrence of [[market failure]]s suggest that this is not always true. In circumstances where property rights are not well-defined, firms or individuals have market power, or there is incomplete information, each [[economic actor]] acting in their own self-interest does not result in the socially optimal outcome. One such example is the [[tragedy of the commons]].  

== The invisible hand in nature ==

== The invisible hand in nature ==