All of the factors just named render the benefits of slave ownership highly dubious. But even if an individual slave-owner chooses to keep slaves despite these disadvantages, he or she would probably nevertheless benefit if slavery were abolished across the entire society, because of the general increased prosperity that would result from such abolition. If former slaves were allowed to function on a normal human level, thus becoming far more productive than before, then everyone, including former slaveholders, could reap the benefits of association and trade with them. In other words, the very existence of the institution of slavery imposes an opportunity cost on slaveholders.

Why then, do all slaveholders not avoid this opportunity cost by freeing their slaves? Unfortunately, if one individual slaveholder were to release only her own slaves, then she could hardly begin to realize the potential benefits of abolition. Instead, she might find herself at a short-run economic disadvantage relative to competitors. If, for instance, she hired workers in the voluntary market to replace slaves in the operation of her cotton plantation, her costs might exceed those of competing cotton producers who used cheaper slave labor. The dilemma of the individual slaveholders is similar to the Prisoners' Dilemma, well-known to game-theorists and economists (): the greater potential benefit of abolition to all slaveholders can be achieved only by concerted action. In practice, such agreement can be achieved by means of a government upholding a free-market system, in which (by definition) slavery would be universally prohibited.