By Josiah Ober, author of The Greeks and the Rational: The Discovery of Practical Reason
In 1949, E.R. Dodds gave the Sather Classical Lectures and soon thereafter published a hugely influential book, The Greeks and the Irrational. When invited to give the 2019 Sather Lectures, I honored his 70th anniversary by choosing a topic that dropped just two letters from Dodds’ title.
Developed from those lectures, my new book The Greeks and the Rational asks two main questions: Why is social cooperation so difficult? And how is it even possible? These questions lie at the heart of contemporary theories of rational agency and ancient Greek theories of practical reasoning. They arise because humans are at once deeply interdependent social creatures (“political animals” in Aristotle’s famous description) and highly sophisticated calculators of advantage. Because we are interdependent members of social communities, it is essential that we cooperate with one another in seeking our common welfare. But because individual self-interest can be maximized by selfishly taking advantage of others’ cooperation, we are constantly at risk of being preyed upon by opportunistic free riders. Societies that over-compensate for that risk are insufficiently cooperative and under-supply common goods. But societies that fail to detect and punish free-riding are vulnerable to the machinations of an unscrupulous few.
Since the mid-20th century, theorists of decision and games, working in the fields of mathematics, economics, and political science have come up with answers to these key questions about humanity. Their answers concern choice and action, and are predicated on a set of intuitions about human motivation, cognition, desire, and belief. Those intuitions were translated into mathematical formulae, so that choice problems and solutions could be expressed algebraically. The resulting body of “rational choice theory” describes the conditions under which self-interested agents will (or won’t) choose cooperation.
Rational choice theory has been highly influential but remains controversial. Some pioneering choice theorists were very concerned with the threat of nuclear warfare. Mathematical techniques have been widely adopted by economists and political scientists seeking to better understand markets and political institutions. As a result, modern choice theory is sometimes regarded as a dehumanizing product of a historically unprecedented era, one in which the terrifying shadow of nuclear catastrophe is uneasily conjoined with a capitalistic celebration of greed.
My book shows that ancient Greek writers – philosophers, historians, and dramatists – shared a set of intuitions about motivation and action that were strikingly similar to the intuitions underpinning contemporary rational choice theory. The Greek intuitions were refined into a general theory that sought to explain the role of self-interest in human behavior. Moreover, anticipating modern choice theorists who teach their readers to be effective strategic reasoners (Avinash Dixit and Barry Nalebuff, The Art of Strategy: A Game Theorist’s Guide to Success in Business and Life), the Greek Sophists made their students experts in the use of strategic reasoning – for good or ill. Although the Greeks never developed the algebraic expression that is so characteristic of modern choice theory, the similarity between ancient and modern explanations of strategic behavior shows that the modern rational choice theory is not merely a product of uniquely modern circumstances.
The ancient Greek theorists of choice are especially worthy of our attention because they conjoin assumptions about individual self-interest with a concern for practical limits on rationality. As experimental psychologists and behavioral economists have shown, real people seldom act in the very narrowly self-interested way that early choice theory predicted. The Greek historians Thucydides and Herodotus were likewise fascinated with the gap between the theory of purely self-interested strategic rationality and observed behavior. Greek lawmakers, most notably in Athens, employed assumptions about rational behavior, and about expected deviations from perfect rationality, in designing and revising the institutions that enabled a mass of citizens to rule themselves. The history of thinking about rational choice is an important yet long neglected facet of the history of democracy.
Plato and Aristotle built the theory of motivation and choice associated with the Sophists into the foundation of their ethical and political theorizing. But they went a big step further. Like the Sophists, they assumed that rational agents gained their desired ends by making strategic choices among available options. The philosophers then added that truly rational agents rationally choose their desires. This advanced form of ethical rationality eventually came to be identified with rationality itself.
My book shows that the Greek philosophers, like the historians and dramatists, were active participants in a broader intellectual community concerned with both theory and practice. A community of ethically rational persons would not raise questions about cooperation. But the Greek philosophers knew that most of us are not saints. They saw that political philosophy must account for the problems of cooperation that arise because humans are at once strategically rational and only imperfectly so.
The big questions about cooperation are not uniquely or even especially modern. The Greeks came up with compelling answers to those questions, and they did so without resorting to advanced mathematics. Greek thinkers could not have solved all of today’s cooperation problems. Yet they can show us that these problems arise because we are human, not because we are modern. By reference to ancient Greek thought, we see more clearly that investigating rational choice-making is not a dehumanizing exercise. It does not reduce humans to mechanical calculators of costs and benefits. Indeed, it is an inherently humanistic undertaking – a vital part of our ongoing inquiry into the distinctive beings we are.