Which C.S. Lewis book examines the dangers of modern education and moral relativism?

The C.S. Lewis book that examines modern education and moral relativism is The Abolition of Man. It was published in 1943 after Lewis delivered the Riddell Memorial Lectures at the University of Durham.

The book is a short work of moral philosophy organized in three chapters: “Men Without Chests,” “The Way,” and “The Abolition of Man.” Lewis argues that denying objective value weakens the human capacity to make sound moral judgments.

His criticism focuses partly on a school textbook that he calls “The Green Book.” Lewis objects to teaching students that value statements are merely expressions of subjective emotion. He links moral education to what he calls the Tao, a term for a broad tradition of objective moral principles shared across cultures.

The title does not mean that Lewis predicted literal human extinction. It refers to a possible transformation of humanity into beings unable to recognize objective value, especially if technological power develops without moral formation.