First published in 1924, Principles of Literary Criticism is a landmark work that transformed the study of literature from a subjective "appreciation" into a rigorous, quasi-scientific discipline. I.A. Richards argues that criticism should be rooted in a firm understanding of psychology—specifically, how the human mind responds to the impulses generated by language and art.

Richards famously introduces the concept of "The Two Uses of Language": the scientific (referential) and the emotive. He posits that the value of poetry lies in its ability to organize our conflicting "appetencies" or impulses, creating a state of psychological balance. This book laid the groundwork for the New Criticism movement, emphasizing "Close Reading" and the idea that a poem should be analyzed as an independent object rather than through the biography of the author or its historical context.