For MacIntyre, the “predecessor culture” is essentially the culture of the Enlightenment, which preceded current-day culture and thought. MacIntyre traces the efforts of philosophers during the Enlightenment to find a rational basis for morality. He concentrates on three philosophers: Hume, Kant, and Kierkegaard (who belonged to a slightly later era but who built on the work of Kant).

Before Hume, the French philosophe Diderot tried but, in MacIntyre’s view, failed to vindicate a conventional morality by explaining it in terms of the satisfaction of desire. Hume continued this line of thought by analyzing moral judgments as “expressions of the feeling, of the passions” (48) and moral rules as rational ways for us to satisfy our desires.

Kant went in the opposite direction and tried to found morality on reason alone, excluding any role of the passions; in fact, he held that an act is moral only when it is an expression of duty rather than of desire. Finally, Kierkegaard went against both Kant and Hume, arguing that morality is rooted in an existential “criterionless fundamental choice” by which we choose what value will guide our moral decision.

In MacIntyre’s analysis, all of these attempts failed, in part because each was in turn founded on a perceived failure by the others.