A kind of cosmological tour de force is here given; the force, or forces, are those between elementary particles governed by conditions of temperature, energy densities, and so on. By the fifth chapter the author has laid the groundwork for a frame-by-frame picture of how it was in the first three minutes, a breathtaking analysis of the evolution of an expanding universe passing from a radiation-dominant to a matter-dominant phase (for which thee and me should be grateful). It is a remarkable achievement by a particle physicist and cosmologist at Harvard and the Smithsonian Astrophysical Observatory. The question of readership is moot. Weinberg writes with a passionate desire to communicate; he uses language colorfully--indeed his main archaeological evidence is the presence of ""fossil"" microwave background radiation in the universe. He also adds mathematical addenda, a glossary, and notes. Still even Sophisticated Reader will have to read twice or thrice unless well-informed of the nuances of special and general relativity theory, the Hubble constant, or the general Cosmological Principle. What makes this slim volume noteworthy is the amount of evidence the author can adduce to support the Big Bang (or possibly oscillating) theory of cosmology. It is this reasoned analysis coupled with fascinating asides about why certain evidence was not sought or considered Which gives philosophers, fellow scientists, and Sophisticated Reader more than a little to think about. While not as elementary as Gamow at his best, this is the first book in a long time that attempts to show the power of physics in explaining the glory of the universe.