This is a book review of To Explain the World: The Discovery of Modern Science by Steven Weinberg. "I am a physicist, not a historian", states Weinberg at the outset. As such, this is not a typical history-of-science book which describes discoveries within the mindset of the time of discovery (or, perhaps unintentionally, the time of writing) but, as the subtitle indicates, concentrates on events which led to the discovery of modern science. The word "discovery" is also important, since Weinberg, as he states in the preface, believes science to be something objective which is discovered and not (as some historians of science hold) some sort of social construct. Despite the wide-ranging title, much or most of the book is about astronomy, simply for the reason that astronomy was often the driving force in the saga of the discovery and development of modern science. Weinberg is selective, intentionally (a point missed or misunderstood by some critics), concentrating on events which led to modern science rather than blind alleys, and on the ideas rather than the people who first discovered them or the society in which they lived. At the same time, in many cases more detail is provided than in other books which cover similar ground, for example the quite extensive differences between the world models of Eudoxus and Ptolemy. I recommend the book to anyone interested in the topic, whatever his or her level of expertise; there is something for everyone here. This is not a conventional history of science, but that is an advantage. While Weinberg departs from the conventional approach in many respects, I think he is correct in doing so, and he states clearly where he differs from convention.