The time has come for nuclear physicists to explain quantum mechanics to the layman. Not ""explain"" in the sense that many popular books have done in describing atomic energy, uranium fission, or the hydrogen bomb, but explain in a more technical sense what quantum numbers--the four digits that completely describe a particle in the atomic nucleus--are all about; what conservation of parity, the Pauli exclusion principle, and strong and weak interactions mean in relation to formulas for nuclear reactions. This is not simple stuff; not intuitive, not easy for the nonmathematical mind. But it is symptomatic of a change or a coming of age in physics. Whereas Einstein's special relativity theory was being handed down to laymen decades ago, we have only now arrived at a time where an ambitious physicist is trying to do the same thing for quantum physics Cohen does a laudable and commendable job. There are gaps; too many. principles stated by fiat; perhaps too much is assumed of prior knowledge of chemistry. But there is the occasional happy metaphor, concrete example, and the overall astonishing reminder that what started out as one of the most abstruse and abstract of disciplines has had far-reaching practical consequences. Some people may despair to read this book, slim though it is. Others may want to re-read it. The repetition would be worth it.