This book investigates whether language can be more accurately understood as a biological phenomenon governed by natural selection rather than a system of prescriptive normative rules. Ruth Garrett Millikan, a prominent philosopher of mind and language, synthesizes a series of essays to challenge the prevailing linguistic assumption that language is defined by rigid, rule-based structures. By applying a biological framework, she argues that linguistic regularities function similarly to biological norms, providing a new lens through which to analyze meaning and communication.

Experts in the philosophy of language recognize this work as a significant contribution to the field, often noting the high level of technical and philosophical density required to engage with Millikan's arguments. Scholars frequently cite this text as a foundational resource for those interested in the intersection of evolutionary biology and linguistic theory.