COMMENT:The contention between a skeptic and a proponent often involves a dispute about what is impossible, so this book, exploring aspects of this concept, is of interest. Biological impossibility teaches us much about it, also in physics and chemistry. Medical impossibilities provide insight into quackery. But the ambiguities are as interesting as the definite statements that can be made; even mathematics is not as clear cut as imagined, and the philosophical questions are intriguing. Impossibility in technology, AI, economics, education are discussed. But the scope of the topic has to be cultural as well; the essays involving mountaineering, law, politics, parenting, poetry, and music are as interesting as the rest.