Mainzer's work is what it advertises itself to be: a compendious handbook of discoveries of symmetries, particularly in mathematics and the natural sciences, and their representation in theories, in philosophy of science, and to a lesser degree in technology and broader culture. Among over a hundred distinguishable areas of study considered are, for example, the following: illustrations and a cursory discussion of symmetrical art from Navajo, Aztec, Indian, and Chinese sources; a few pages on the mechanism of the ancient Chinese south-pointing carriage; twenty pages on the history of constructions of regular polygons and Platonic and other geometric solids; symmetries in historical and recent space-time theories and in thermodynamics and chaotic systems; antisymmetry in DNA synthesis and structural symmetries and asymmetries in organisms; and even metaphorical "symmetry breaking" in decentered postmodern art and critical theory.

Symmetry has become a particularly important topic in philosophy of science, especially since the publication by Bas C. van Fraassen of Laws and Symmetry (Clarendon: Oxford, 1989.). Van Fraassen argues that the idea of necessity that underlies law explanation and causation is a vestige of 17th century science, and an account of science as a process of constructing models that express mathematical relations, symmetries, and invariances provides adequate representation of the phenomena of nature. Mainzer's interest lies in a related project, determining the prospects for a unification of theories among the sciences, or the unification of models. His collection represents a useful resource for those attempting to understand the prospects for unification and the degree to which symmetry arguments pervade scientific explanation across fields. Mainzer is a philosopher of mathematics and physics, and his extended discussion of physics, especially quantum mechanics and particles, is the most developed portion of the volume, and provides a core that connects a good deal, though not all, of the balance of the handbook. Consequently, chemistry is considered primarily in a 30-page historical treatment of crystal classification, leading to a discussion of mathematical group theory, and molecular handedness. Homochirality in nature also comes in for brief treatment. A short discussion of molecular structures introduces the topic of the prospects and purposes of a unification of theories by a reduction of stereochemistry to quantum mechanics, given that "our models and images are always only more or less drastic simplifications and abstractions of complex relationships" in nature itself.