The 18th-century philosopher Adam Smith is frequently described as the father of capitalism and is well known for praising what he called the market’s “invisible hand.” But he also developed complex theories of justice, said Daniel Klein, an economics professor at George Mason University, in a lecture Tuesday evening.

“My approach is very Talmudic,” Klein said, promising to deliver an “exegesis of Smith.” He gave the approximately 30 attendees in MacMillan 115 handouts filled with graphs, block quotes and analytical notes to guide attendees through the presentation.

Klein argued that Smith identified multiple facets of justice beyond the well-known idea of “commutative justice,” which was Smith’s term for “rules against not messing with other people’s stuff,” Klein said.

One of the handouts included Smith’s definition of “distributive justice,” which instructs individuals to “conceive for (your neighbor) all that love, respect and esteem, which his character, his situation and his connection with ourselves, render suitable and proper for us to feel.”

Another facet, which Smith never named and Klein called “estimative justice,” explained justice as making an estimation that fully recognizes an object’s value, Klein said. Smith also wrote of a fourth kind of justice stemming from Plato’s theories that is a kind of “comprehensive estimative justice,” Klein said.

“The rules of commutative justice are like the rules of grammar,” Klein said, comparing the other justices to what Smith called “the rules which critics lay down for the attainment of what is sublime and elegant in composition.” In other words, it is clear when one has violated commutative justice but more “loose” or “vague” when one has violated distributive or estimative justice, Klein said.

If Smith were to apply his theories in practice, he would not support a welfare state but would endorse taxation for purposes beyond the protection of private property, Klein said. Smith had ties to his government and for practical reasons might not have wanted to endorse great changes to the status quo, he said. Smith’s writings did not extensively discuss the “poor laws” instituted in his country at the time.

Smith believed that, with certain exceptions allowed to the government, no one should be “messing with other people’s stuff” and thus infringing on commutative justice, Klein said.

An action is unjust only when it violates commutative justice or, in terms of distributive justice and estimative justice, “falls below the point of propriety” — what Smith saw as a middle ground of acceptability, Klein said.

During a question-and-answer session following the presentation, Matt Mettler ’13 raised concerns that Smith’s complex theory of justice and his belief in human equality could be used to justify economic redistribution and “all sorts of things that it seems Smith is not necessarily for.”

Adam Shur ’14, president of Students for Liberty, the student organization that hosted the event, said he understood Mettler’s question. The ambiguity of “the point of propriety” makes putting Smith’s theories into practice challenging, he agreed.

Members of Students for Liberty, a group that aims to promote discussion and education on freedom and rights, invited Klein to speak because they thought he could provide a unique perspective on the “different ways people come to the ideas of libertarianism,” Shur said.