The potential for reason and critical scrutiny to address social issues is explored, set against the backdrop of a century marked by significant atrocities. W. B. Yeats’s annotation on Nietzsche’s work is recounted, questioning Nietzsche’s pessimistic view of humanity, which seemed to be validated by the horrors of the 20th century. Sen discusses Jonathan Glover, who, drawing from the last century’s moral history, calls for a reflection on the darker aspects of human nature, advocating for a guide by reason over tradition. Glover critiques the Enlightenment’s naive view of human psychology but acknowledges the role of instincts when reasoning falls short, as illustrated by Nikolai Bukharin’s struggle between natural revulsion and ideological rigidity during Stalin’s regime.

Emperor Akbar’s 16th-century policies, Sen states, exemplify the early use of reason to promote religious harmony, a pertinent approach that contrasts with the uncritical celebration of the millennium. The importance of reason is highlighted as a hope for guiding humanity, as supported by Kenzaburo Oe’s democratic ideals, and Sen concludes that fostering human responses such as respect and sympathy is crucial to restraining atrocity; Sen advocates for a complex psychological understanding beyond the simplistic Enlightenment perspective.

The critique of the Enlightenment distinguishes between the power of reasoning and the notion of human perfectibility.