This book investigates whether central philosophical problems possess objective, singular answers or if they are inherently dependent on the arbitrary definitions of key terms. Peter Unger, a prominent philosopher, examines the persistent nature of debates surrounding knowledge, skepticism, free will, and causation. He argues that the conflicting conclusions reached by various schools of thought often stem from differing, yet equally arbitrary, semantic assumptions regarding fundamental concepts. By challenging the possibility of definitive solutions, Unger proposes a framework of philosophical relativity that questions the traditional pursuit of absolute truth in these domains.

Philosophers and students of the discipline frequently note the dense, analytical nature of Unger's prose. Experts highlight this work as a significant contribution to meta-philosophical discourse, often citing it for its provocative stance on the limitations of traditional inquiry.