This work by James Maffie both praises and goes far beyond the preliminary findings that Miguel León Portilla presented in his landmark work La filosofia Nahuatl (1956, translated as Aztec Thought and Culture, 1963). Maffie’s contribution is a mature, rounded, and nuanced look at the philosophical underpinnings of a culture that has been widely misunderstood through history. This is a very cogent and well-written analysis of the philosophical bases of Aztec civilization. Maffie uses the term Aztec because of its utility rather than the more cumbersome Tenochca-Mexica, as he explains early on.Unlike earlier scholarship, Maffie approaches the issue of Aztec philosophy by looking into metaphysics: “how its claims, concepts, metaphors, and arguments fit together” (3). But to accomplish that, it is necessary to determine exactly what the Aztecs believed. At multiple points in his exposition, he considers countering arguments. Certainly, many argue that non-Western philosophy is inherently oxymoronic. Maffie quickly dispels this notion to allow us to focus on the underlying issues of Aztec metaphysics.Maffie’s description of Aztec metaphysics is seemingly simple. For the Aztecs, throughout everything, at the essential level of all things, there is a power, energy, life-force, called teotl. Yet it is not something that exists, it is continually becoming. Rather than being polytheistic, having many gods (which they did), Maffie sees the Aztecs as pantheistic, because the story of teotl is the same as the history of the self-becoming and self-unfolding of all existence. Linked to teotl is the concept of inamic. This term is used in Nahuatl to describe one’s spouse. For Maffie, it is “agonistic inamic unity” (13), in other words, the pairing of one power with a second that might be its polar opposite, but not necessarily in a conflictive way. The concept has to do more with relations than with conflict, although the two poles might be competitive or antagonistic. Male requires that there be female. Wet demands that there be dry.Within the process of becoming and of the competition within inamic, there are three directions, relations, or influences also at work. All three are what Maffie characterizes as “motion-change.” The first of these is olin. Broadly defined, this is simple movement, a curving, back-and-forth, pulsation found in breathing, beating hearts, and the movement of the sun. The second is malinalli, associated with twisting and turning, such as making thread, working a fire drill, or our bodies digesting food. If olin defines life and death cycles, then malinalli is the transformation of energy within the cycles. Lastly, there was nepantla. This is the notion of not here and not there, but in-betweenness. Within the concept of motion-change, nepantla is the most fundamental and is essential to the concept of teotl.Aztec metaphysics uses these tools to envision reality as a fabric, a singular entity of space-time in which teotl is continually becoming, vibrating through the essential movements of the universe, linked up in inamic relationships that define the entity. In the fabric of reality, nepantla defines the weaving process, while olin is the weft (horizontal) and malinalli is the warp (vertical). In the end, humanity is walking through life, pulled on all sides, choosing the middle path. It is as though we walk along a jagged precipice, with canyons on either side. Humanity must walk the middle path, the nepantla. We live in the Fifth Sun, the Sun of motion, and all of existence is marked by the movement of teotl within, and working to become, creation.Maffie’s argument is at the same time simple and straightforward as it is complex and nuanced. Stripped away, the underlying concepts are clear, relational, and profound. Yet Maffie musters a wealth of details, logic, and exposition to weave many discrete points together to make the ostensibly simple argument. A brief review can hardly begin to do justice to the elegance of the logic, the complexity of the argument, and the many bits of information that Maffie uses to prove his points. In a work this complex and this detailed, no doubt some will find flaws. But taken as a whole, it is a masterful exposition of a fascinating topic.